1 ( 1 Oct 01) General Atomic and Molecular Electronic Structure System GAMESS User's Guide Department of Chemistry Iowa State University Ames, IA 50011 Section 1 - INTRO.DOC - Overview Section 2 - INPUT.DOC - Input Description Section 3 - TESTS.DOC - Input Examples Section 4 - REFS.DOC - Further Information Section 5 - PROG.DOC - Programmer's Reference Section 6 - IRON.DOC - Hardware Specifics GGG A M M EEEE SSSS SSSS G A A MM MM E S S G GG A A M M M EEE SSS SSS G G AAAAA M M E S S GGG A A M M EEEE SSSS SSSS Original program assembled by the staff of the NRCC: M. Dupuis, D. Spangler, and J. J. Wendoloski National Resource for Computations in Chemistry Software Catalog, University of California: Berkeley, CA (1980), Program QG01 This version of GAMESS is described in M.W.Schmidt, K.K.Baldridge, J.A.Boatz, S.T.Elbert, M.S.Gordon, J.H.Jensen, S.Koseki, N.Matsunaga, K.A.Nguyen, S.J.Su, T.L.Windus, M.Dupuis, J.A.Montgomery J.Comput.Chem. 14, 1347-1363(1993) Another information source is http://www.msg.ameslab.gov/GAMESS/GAMESS.html Graphical display of results is possible using MacMolPlt, a back end visualizer as well as front end input preparer, available for the MacIntosh computer only. MacMolPlt can be downloaded freely at the web site just given. There is a GAMESS discussion group originally started by Gotthard Saghi-Szabo at the University of Maryland. For info, see http://mineral.umd.edu/gamess-users The discussions are archived at http://lacebark.ntu.edu.au/gamess/ Questions about GAMESS may be addressed to: Mike Schmidt = mike@si.fi.ameslab.gov = 515-294-9796 E-mail is much, much, much preferred to phone calls! 1 A wide range of quantum chemical computations are possible using GAMESS, which 1. Calculates RHF, UHF, ROHF, GVB, or MCSCF self- consistent field molecular wavefunctions. 2. Calculates CI or MP2 corrections to the energy of these SCF functions. 3. Calculates Density Functional Theory wavefunctions for RHF, UHF, or ROHF ansatz. 4. Calculates semi-empirical MNDO, AM1, or PM3 RHF, UHF, or ROHF wavefunctions. 5. Calculates analytic energy gradients for all SCF and DFT wavefunctions, plus closed shell MP2 or CI. 6. Optimizes molecular geometries using the energy gradient, in terms of Cartesian or internal coords. 7. Searches for potential energy surface saddle points. 8. Computes the energy hessian, and thus normal modes, vibrational frequencies, and IR intensities. The Raman intensities are an optional follow-on job. 9. Obtains anharmonic vibrational frequencies and intensities (fundamentals or overtones). 10. Traces the intrinsic reaction path from a saddle point to reactants or products. 11. Traces gradient extremal curves, which may lead from one stationary point such as a minimum to another, which might be a saddle point. 12. Follows the dynamic reaction coordinate, a classical mechanics trajectory on the potential energy surface. 13. Computes radiative transition probabilities. 14. Evaluates spin-orbit coupled wavefunctions. 15. Applies finite electric fields, extracting the molecule's linear polarizability, and first and second order hyperpolarizabilities. 16. Evaluates analytic frequency dependent non-linear optical polarizability properties, for RHF functions. 17. Obtains localized orbitals by the Foster-Boys, Edmiston-Ruedenberg, or Pipek-Mezey methods, with optional SCF or MP2 energy analysis of the LMOs. 1 18. Calculates the following molecular properties: a. dipole, quadrupole, and octupole moments b. electrostatic potential c. electric field and electric field gradients d. electron density and spin density e. Mulliken and Lowdin population analysis f. virial theorem and energy components g. Stone's distributed multipole analysis 19. Models solvent effects by a. effective fragment potentials (EFP) b. polarizable continuum model (PCM) c. conductor-like screening model (COSMO) d. self-consistent reaction field (SCRF) 20. When combined with the add-on TINKER molecular mechanics program, performs Surface IMOMM or IMOMM QM/MM type simulations. Download from http://php.scl.ameslab.gov/GAMESS/tinker/tinker.tar.Z A quick summary of the current program capabilities is given below. SCFTYP= RHF ROHF UHF GVB MCSCF --- ---- --- --- ----- Energy CDP CDP CDP CDP CDP analytic gradient CDP CDP CDP CDP CDP numerical Hessian CDP CDP CDP CDP CDP analytic Hessian CDP CDP - CDP - MP2 energy CDP CDP CDP - CP MP2 gradient CDP - - - - CI energy CDP CDP - CDP CDP CI gradient CD - - - - DFT energy CDP CDP CDP - - DFT gradient CDP CDP CDP - - MOPAC energy yes yes yes yes - MOPAC gradient yes yes yes - - C= conventional storage of AO integrals on disk D= direct evaluation of AO integrals P= parallel execution 1 History of GAMESS GAMESS was put together from several existing quantum chemistry programs, particularly HONDO, by the staff of the National Resources for Computations in Chemistry. The NRCC project (1 Oct 77 to 30 Sep 81) was funded by NSF and DOE, and was limited to the field of chemistry. The NRCC staff added new capabilities to GAMESS as well. Besides providing public access to the code on the CDC 7600 at the site of the NRCC (the Lawrence Berkeley Laboratory), the NRCC made copies of the program source code (for a VAX) available to users at other sites. This manual is a completely rewritten version of the original documentation for GAMESS. Any errors found in this documentation, or the program itself, should not be attributed to the original NRCC authors. The present version of the program has undergone many changes since the NRCC days. This occurred at North Dakota State University prior to 1992, and now continues at Iowa State University. A number of persons (some of whom have now left the Gordon group) have made contributions: Jerry Boatz, Kim Baldridge, and Shiro Koseki at NDSU; Kiet Nguyen, Jan Jensen, Theresa Windus, Nikita Matsunaga, Shujun Su, Paul Day, Brett Bode, Simon Webb, Wei Chen, Tetsuya Taketsugu, Galina Chaban, Grant Merrill, Graham Fletcher, Kurt Glaesemann, Dmitri Fedorov, Cheol Choi, and Rob Bell at ISU; plus Frank Jensen at Odense U., Mariusz Klobukowski at U.Alberta, Henry Kurtz at U.Memphis, Brenda Lam at U.Ottawa, John Montgomery at United Technologies. Haruyuki Nakano at U.Tokyo It would be difficult to overestimate the contributions Michel Dupuis has made to this program, both in its original form, and since. This includes the donation of code from HONDO, and numerous suggestions for other improvements. The continued development of this program from 1982 on can be directly attributed to the nurturing environment provided by Professor Mark Gordon. Funding for much of the development work on GAMESS is provided by the Air Force Office of Scientific Research. 1 In late 1987, NDSU and IBM reached a Joint Study Agreement. One goal of this JSA was the development of a version of GAMESS which is vectorized for the IBM 3090's Vector Facility, which was accomplished by the fall of 1988. This phase of the JSA led to a program which is also considerably faster in scalar mode as well. The second phase of the JSA, which ended in 1990, was to enhance GAMESS' scientific capabilities. These additions include analytic hessians, ECPs, MP2, spin-orbit coupling and radiative transitions, and so on. Everyone who uses the current version of GAMESS owes thanks to IBM in general, and Michel Dupuis of IBM Kingston in particular, for their sponsorship of the current version of GAMESS. During the first six months of 1990, Digital awarded a Innovator's Program grant to NDSU. The purpose of this grant was to ensure GAMESS would run on the DECstation, and to develop graphical display programs. As a result, the companion programs MOLPLT, PLTORB, DENDIF, and MEPMAP were modernized for the X-windows environment, and interfaced to GAMESS. These programs now run under the Digital Unix or VMS windowing environments, and many other X-windows environments as well. The ability to visualize the molecular structures, orbitals, and electrostatic potentials is a significant improvement. Parallelization of GAMESS began in 1991, with most of the work and design strategy done by Theresa Windus. This multi-year process benefits greatly from the long term support of GAMESS by the AFOSR, as well as the ARPA sponsorship of the Touchstone Delta experimental computer. As of July 1, 1992, the development of GAMESS moved to Iowa State University at the Ames Laboratory. The DoD awarded a CHSSI grant to ISU in 1996 to extend that scalability of existing parallel methods, and more importantly develop new techniques. This brought Graham Fletcher on board as a postdoc, and has led to the introduction of the Distributed Data Interface style of programming. The rest of this section gives more specific credit to the sources of various parts of the program. * * * * GAMESS is a synthesis, with many major modifications, of several programs. A large part of the program is from HONDO 5. For sp basis functions, Gaussian76 sp integrals and Gaussian80 sp gradient integrals are used. Both the sp rotated axis integrals and the sp gradient packages have been rewritten in 2001 by Jose Maria Sierra of Synstar Computer Services in Madrid, Spain. 1 Rys polynomials are used for any basis functions with higher angular momentum. Redimensioning of HONDO 1e- and 2e- Rys integral routines to handle spdfg basis sets was done by Theresa Windus at North Dakota State University. The current spdfg gradient package consists of HONDO8 code for higher angular momentum, and was adapted into GAMESS by Brett Bode at Iowa State University. The use of quantum fast multipole methods for avoiding long range integral evaluation in large molecules was programmed by Cheol Choi at Iowa State and at Kyungpook National University, and included in GAMESS in 2001. The ECP code goes back to Louis Kahn, with gradient modifications originally made by K.Kitaura, S.Obara, and K.Morokuma at IMS in Japan. The code was adapted to HONDO by Stevens, Basch, and Krauss, from whence Kiet Nguyen adapted it to GAMESS at NDSU. Modifications for f functions were made by Drora Cohen and Brett Bode. This code was completely rewritten to use spdfg basis sets, to exploit shell structure during integral evaluation, and to add the capability of analytic second derivatives by Brett Bode at ISU in 1997-1998. Changes in the manner of entering the basis set, and the atomic coordinates (including Z-matrix forms) are due to Jan Jensen at North Dakota State University. The direct SCF implementation was done at NDSU, guided by a pilot code for the RHF case by Frank Jensen. The Direct Inversion in the Iterative Subspace (DIIS) convergence procedure was implemented by Brenda Lam (then at the University of Houston), for RHF and UHF functions. The UHF code was taught to do high spin ROHF by John Montgomery at United Technologies, who extended DIIS use to ROHF and the one pair GVB case. Additional GVB-DIIS cases were programmed by Galina Chaban at ISU. The GVB part is a heavily modified version of GVBONE. The FULLNR and FOCAS MCSCF programs were contributed by Michel Dupuis of IBM from the HONDO program. The approximate 2nd order SCF was implemented by Galina Chaban at Iowa State University. SOSCF is provided for RHF, ROHF, GVB, and MCSCF cases. The Jacobi 2 by 2 orbital rotation scheme for MCSCF orbital optimization was written by Joe Ivanic and Klaus Ruedenberg at Iowa State University in 2001. 1 The Ames Laboratory determinant full CI code was written by Joe Ivanic and Klaus Ruedenberg. As befits code written by an Australian living in Iowa, it was interfaced to GAMESS during an extremely cordial visit to Australia National University in January 1998. An update by Joe in October 2000 exploits Abelian point group symmetry. A general CI program based on selected determinants was added by Joe and Klaus in July 2001. The GUGA CI is based on Brooks and Schaefer's unitary group program which was modified to run within GAMESS, using a Davidson eigenvector method written by Steve Elbert. Programming of the analytic CI gradient was done by Simon Webb at Iowa State University. The sequential MP2 code was adapted from HONDO by Nikita Matsunaga at Iowa State, who also added the RMP2 open shell option in 1992. The MP2 gradient code is also from HONDO, and was adapted to GAMESS in 1995 by Simon Webb and Nikita Matsunaga. In 1996, Simon Webb added the frozen core gradient option at ISU. Haruyuki Nakano from the University of Tokyo interfaced his multireference MCQDPT code to GAMESS during a 1996 visit to ISU. Parallelization of the multireference PT code was done by Hiroaki Umeda at Mie University and included into GAMESS in 2001. The parallel MP2 code is a descendent of work done for GAMESS-UK by Graham Fletcher, Alistair Rendell, and Paul Sherwood at Daresbury. This was adapted to GAMESS at ISU by Graham Fletcher in 1999, after some grief in developing the necessary DDI infrastructure. The grid-free DFT energy and gradient code was written by Kurt Glaesemann at Iowa State University, starting from the code of Almlof and Zheng, adding four center overlap integrals, a gradient program, developing the auxiliary basis option, and adding some functionals. This was included in GAMESS in 1999. The grid based DFT program was written in 2001 at the University of Tokyo, by Takao Tsuneda, Muneaki Kamiya, Susumu Yanagisawa, and Dmitri Fedorov. Many improvements such as use of symmetry and initial small grid during the numerical quadrature, functional development and coding, and the ability to run in parallel come from this group. The original program prior to these numerous changes is from Nevin Oliphant, Hideo Sekino, and Rod Bartlett at QTP. Incorporation of enough MOPAC version 6 routines to run PM3, AM1, and MNDO calculations from within GAMESS was done by Jan Jensen at North Dakota State University. 1 The numerical force constant computation and normal mode analysis was adapted from Andy Komornicki's GRADSCF program, with decomposition of normal modes in internal coordinates written at NDSU by Jerry Boatz. The code for the analytic computation of RHF Hessians was contributed by Michel Dupuis of IBM from HONDO 7, with open shell CPHF code written at NDSU. The TCSCF CPHF code is the result of a collaboration between NDSU and John Montgomery at United Technologies. IR intensities and analytic polarizabilities during hessian runs were programmed by Simon Webb at ISU. Code for Raman intensity prediction was written at Tokyo Metropolitan University in April 2000. The vibrational SCF and MP2 anharmonic frequency code for fundamental modes and overtones was written by Galina Chaban, Joon Jung, and Benny Gerber at U.California-Irvine and Hebrew University of Jerusalem, and included in GAMESS in 2000. The solver was modified to perform degenerate perturbation theory for more accurate results by Nikita Matsunaga at Long Island University in 2001. Most geometry search procedures in GAMESS (NR, RFO, QA, and CONOPT) were developed by Frank Jensen of Odense University. These methods are adapted to use GAMESS symmetry, and Cartesian or internal coordinates. The non-gradient optimization so aptly described as "trudge" was adapted from HONDO 7 by Mariusz Klobukowski at U.Alberta, who added the option for CI optimizations. The intrinsic reaction coordinate pathfinder was written at North Dakota State University, and modified later for new integration methods by Kim Baldridge. The Gonzales-Schelegel IRC stepper was incorporated by Shujun Su at Iowa State, based on pilot code from Frank Jensen. The code for the Dynamic Reaction Coordinate was developed by Tetsuya Taketsugu at Ochanomizu U. and U. of Tokyo, and added to GAMESS by him at ISU in 1994. The two algorithms for tracing gradient extremals were programmed by Frank Jensen at Odense University. The program for Monte Carlo generation of trial structures along with a simulated annealing protocol was written by Paul Day at Wright-Patterson Air Force Base. Modifications to this were made by Pradipta Bandyopadhyay at ISU, and the code was included in 2001. The surface scanning option was implemented by Richard Muller at the University of Southern California. 1 Most polarizability calculations in GAMESS were implemented by Henry Kurtz of the University of Memphis. This includes a general numerical differentiation based on application of finite electric fields, and a fully analytic calculation of static and frequency dependent NLO properties for closed shell systems. The latter code was based on a MOPAC implementation by Prakashan Korambath at U. Memphis. The radiative transition moment and Zeff spin-orbit coupling modules were written by Shiro Koseki at both North Dakota State University and at Mie University. The full Breit-Pauli spin-orbit coupling integral package was written by Thomas Furlani. This code was incorporated into GAMESS by Dmitri Fedorov at Iowa State University in 1997, who generalized the spin-orbit coupling matrix element code generously provided by Thomas Furlani (restricted to an active space of two electrons in two orbitals), with assistance from visits to ISU by Thomas Furlani and Shiro Koseki. Dmitri Fedorov has since generalized the full two electron approach to allow for any spins, for more than two spin multiplicities at a time, and a partial treatment of the the two electron terms that runs in time similar to the one electron operator. Space and spin symmetries are exploited to speed up the runs. Dmitri Fedorov programmed the SO-MCQDPT options at the University of Tokyo in 2001. Inclusion of relativistic effects by the Relativistic scheme of Elimination of Small Components (RESC) method, was developed by Takahito Nakajima and Kimihiko Hirao at the University of Tokyo. This code was written by Takahito Nakajima and consequently adapted into GAMESS by Dmitri Fedorov, who has extended the methodology in March 2000 to the computation of gradients. RESC provides both scalar (spin free) and vector (spin-dependent) relativistic corrections. The Normalized Elimination of Small Components (NESC) was programmed by Dmitri Fedorov at ISU and the University of Tokyo. Special thanks are due to Kenneth Dyall for his assistance in providing check values. Extension of NESC to include gradient computation was also done by Dmitri. Edmiston-Ruedenberg energy localization is done with a version of the ALIS program "LOCL", modified at NDSU to run inside GAMESS. Foster-Boys localization is based on a highly modified version of QCPE program 354 by D.Boerth, J.A.Hasmall, and A.Streitweiser. John Montgomery implemented the population localization. The LCD SCF decomposition and the MP2 decomposition were written by Jan Jensen at Iowa State in 1994. Point Determined Charges were implemented by Mark Spackman at the University of New England, Australia. 1 Delocalized internal coordinates were implemented by Jim Shoemaker at the Air Force Institute of Technology in 1997, and put online in GAMESS by Cheol Choi at ISU after further improvements in 1998. The Morokuma decomposition was implemented by Wei Chen at Iowa State University. Development of the EFP method began in the group of Walt Stevens at NIST's Center for Advanced Research in Biotechnology (CARB) in 1988. Walt is the originator of this method, and has provided both guidance and some financial support to ISU for its continued development. Mark Gordon's group's participation began in 1989-90 as discussions during a year Mark spent in the DC area, and became more serious in 1991 with a visit by Jan Jensen to CARB. At this time the method worked for the energy, and gradient with respect to the ab initio nuclei, for one fragment only. Jan has assisted with most aspects of the multi-fragment development since. Paul Day at NDSU and ISU derived and implemented the gradient with respect to fragments, and programmed EFP geometry optimization. Wei Chen at ISU debugged many parts of the EFP energy and gradient, developed the code for following IRCs, improved geometry searches, and fitted much more accurate repulsive potentials. Simon Webb at ISU programmed the current self-consistency process for the induced dipoles. The EFP method was sufficiently developed, tested, and described to be released in Sept 1996. The SCRF solvent model was implemented by Dave Garmer at CARB, and was adapted to GAMESS by Jan Jensen and Simon Webb at Iowa State University. The COSMO model was developed by Andreas Klamt and Kim Baldridge, at San Diego Supercomputer Center. It was included into GAMESS by Laura Gregerson in March 2000 during a visit to Ames. The PCM code originates in the group of Jacopo Tomasi at the University of Pisa. Benedetta Mennucci was instrumental in interfacing the PCM code to GAMESS, in 1997, and answering many technical questions about the code, the methodology, and the documentation. In 2000, Benedetta Menucci provided code implementing an improved IEF solver for the PCM surface charges. This new code was interfaced to the effective fragment potential method by Pradipta Bandyopadhyay at Iowa State University. 1 Distribution Policy To get a copy, please fill out the application form available on http://www.msg.ameslab.gov/GAMESS/GAMESS.html Persons receiving copies of GAMESS are requested to acknowledge that they will not make copies of GAMESS for use at other sites, or incorporate any portion of GAMESS into any other program, without receiving permission to do so from ISU. This is done by signing and returning a straightforward copyright letter. If you know anyone who wants a copy of GAMESS, please refer them to us for the most up to date version available. No large program can ever be guaranteed to be free of bugs, and GAMESS is no exception. If you would like to receive an updated version (fewer bugs, and with new capabilities) contact Mike over the net. You should probably allow a year or so to pass for enough significant changes to accumulate. 1 Input Philosophy Input to GAMESS may be in upper or lower case. There are three types of input groups in GAMESS: 1. A pseudo-namelist, free format, keyword driven group. Almost all input groups fall into this first category. 2. A free format group which does not use keywords. The only examples of this category are $DATA, $ECP, $POINTS, and $STONE. 3. Formatted data. This data is never typed by the user, but rather is generated in the correct format by some earlier GAMESS run. All input groups begin with a $ sign in column 2, followed by a name identifying that group. The group name should be the only item appearing on the input line for any group in category 2 or 3. All input groups terminate with a $END. For any group in category 2 and 3, the $END must appear beginning in column 2, and thus is the only item on that input line. Type 1 groups may have keyword input on the same line as the group name, and the $END may appear anywhere. Because each group has a unique name, the groups may be given in any order desired. In fact, multiple occurrences of category 1 groups are permissible. * * * Most of the groups can be omitted if the program defaults are adequate. An exception is $DATA, which is always required. A typical free format $DATA group is $DATA STO-3G test case for water CNV 2 OXYGEN 8.0 STO 3 HYDROGEN 1.0 -0.758 0.0 0.545 STO 3 $END 1 Here, position is important. For example, the atom name must be followed by the nuclear charge and then the x,y,z coordinates. Note that missing values will be read as zero, so that the oxygen is placed at the origin. The zero Y coordinate must be given for the hydrogen, so that the final number is taken as Z. The free format scanner code used to read $DATA is adapted from the ALIS program, and is described in the documentation for the graphics programs which accompany GAMESS. Note that the characters ;>! mean something special to the free format scanner, and so use of these characters in $DATA and $ECP should probably be avoided. Because the default type of calculation is a single point (geometry) closed shell SCF, the $DATA group shown is the only input required to do a RHF/STO-3G water calculation. * * * As mentioned, the most common type of input is a namelist-like, keyword driven, free format group. These groups must begin with the $ sign in column 2, but have no further format restrictions. You are not allowed to abbreviate the keywords, or any string value they might expect. They are terminated by a $END string, appearing anywhere. The groups may extend over more than one physical card. In fact, you can give a particular group more than once, as multiple occurrences will be found and processed. We can rewrite the STO-3G water calculation using the keyword groups $CONTRL and $BASIS as $CONTRL SCFTYP=RHF RUNTYP=ENERGY $END $BASIS GBASIS=STO NGAUSS=3 $END $DATA STO-3G TEST CASE FOR WATER Cnv 2 Oxygen 8.0 0.0 0.0 0.0 Hydrogen 1.0 -0.758 0.0 0.545 $END Keywords may expect logical, integer, floating point, or string values. Group names and keywords never exceed 6 characters. String values assigned to keywords never exceed 8 characters. Spaces or commas may be used to separate items: $CONTRL MULT=3 SCFTYP=UHF,TIMLIM=30.0 $END Floating point numbers need not include the decimal, and may be given in exponential form, i.e. TIMLIM=30, TIMLIM=3.E1, and TIMLIM=3.0D+01 are all equivalent. 1 Numerical values follow the FORTRAN variable name convention. All keywords which expect an integer value begin with the letters I-N, and all keywords which expect a floating point value begin with A-H or O-Z. String or logical keywords may begin with any letter. Some keyword variables are actually arrays. Array elements are entered by specifying the desired subscript: $SCF NO(1)=1 NO(2)=1 $END When contiguous array elements are given this may be given in a shorter form: $SCF NO(1)=1,1 $END When just one value is given to the first element of an array, the subscript may be omitted: $SCF NO=1 NO(2)=1 $END Logical variables can be .TRUE. or .FALSE. or .T. or .F. The periods are required. The program rewinds the input file before searching for the namelist group it needs. This means that the order in which the namelist groups are given is immaterial, and that comment cards may be placed between namelist groups. Furthermore, the input file is read all the way through for each free-form namelist so multiple occurrences will be processed, although only the LAST occurrence of a variable will be accepted. Comment fields within a free-form namelist group are turned on and off by an exclamation point (!). Comments may also be placed after the $END's of free format namelist groups. Usually, comments are placed in between groups, $CONTRL SCFTYP=RHF RUNTYP=GRADIENT $END --$CONTRL EXETYP=CHECK $END $DATA molecule goes here... The second $CONTRL is not read, because it does not have a blank and a $ in the first two columns. Here a careful user has executed a CHECK job, and is now running the real calculation. The CHECK card is now just a comment line. 1 * * * The final form of input is the fixed format group. These groups must be given IN CAPITAL LETTERS only! This includes the beginning $NAME and closing $END cards, as well as the group contents. The formatted groups are $VEC, $HESS, $GRAD, $DIPDR, and $VIB. Each of these is produced by some earlier GAMESS run, in exactly the correct format for reuse. Thus, the format by which they are read is not documented in section 2 of this manual. * * * Each group is described in the Input Description section. Fixed format groups are indicated as such, and the conditions for which each group is required and/or relevant are stated. There are a number of examples of GAMESS input given in the Input Examples section of this manual. * * * Input Checking Because some of the data in the input file may not be processed until well into a lengthy run, a facility to check the validity of the input has been provided. If EXETYP=CHECK is specified in the $CONTRL group, GAMESS will run without doing much real work so that all the input sections can be executed and the data checked for correct syntax and validity to the extent possible. The one-electron integrals are evaluated and the distinct row table is generated. Problems involving insufficient memory can be identified at this stage. To help avoid the inadvertent absence of data, which may result in the inappropriate use of default values, GAMESS will report the absence of any control group it tries to read in CHECK mode. This is of some value in determining which control groups are applicable to a particular problem. The use of EXETYP=CHECK is HIGHLY recommended for the initial execution of a new problem. 1 Program limitations GAMESS can use an arbitrary Gaussian basis of spdfg type for computation of the energy or gradient. Some restrictions apply, for example, analytic hessians are limited to spd basis sets. This program is limited to a total of 500 atoms. The total number of shells cannot exceed 1000, containing no more than 5000 symmetry unique Gaussian primitives. Each contraction can contain no more than 30 gaussians. The total number of contracted basis functions, or AOs, cannot exceed 2047. You may use up to 50 effective fragments, of at most 5 types, containing up to 100 expansion points. In practice, you will probably run out of CPU or disk before you encounter any of these limitations. See Section 5 of this manual for information about changing any of these limits, or minimizing program memory use. Except for these limits, the program is basically dimension limitation free. Memory allocations other than these limits are dynamic. 1 Restart Capability The program checks for CPU time, and will stop if time is running short. Restart data are printed and punched out automatically, so the run can be restarted where it left off. At present all SCF modules will place the current orbitals on the punch file if the maximum number of iterations is reached. These orbitals may be used in conjunction with the GUESS=MOREAD option to restart the iterations where they quit. Also, if the TIMLIM option is used to specify a time limit just slighlty less than the job's batch time limit, GAMESS will halt if there is insufficient time to complete another full iteration, and the current orbitals will be punched. When searching for equilibrium geometries or saddle points, if time runs short, or the maximum number of steps is exceeded, the updated hessian matrix is punched for restart. Optimization runs can also be restarted with the dictionary file. See $STATPT for details. Force constant matrix runs can be restarted from cards. See the $VIB group for details. The two electron integrals may be reused. The Newton-Raphson formula tape for MCSCF runs can be saved and reused. * * * * The binary file restart options are rarely used, and so may not work well (or at all). Restarts which change the card input (adding a partially converged $VEC, or updating the coordinates in $DATA, etc.) are far more likely to be sucessful than restarts from the DAF file. 1 (15 Nov 01) ********************************* * * * Section 2 - Input Description * * * ********************************* This section of the manual describes the input to GAMESS. The section is written in a reference, rather than tutorial fashion. However, there are frequent reminders that more information can be found on a particular input group, or type of calculation, in the 'Further Information' section of this manual. There are also a number of examples shown in the 'Input Examples' section. It is useful to note that this chapter of the manual can be searched online by means of the "gmshelp" command, if your computer is of the Unix type. A command such as "gmshelp scf" will display the $SCF input group. With no arguments, the gmshelp command will show you all input group names. Type "q" to exit the pager, and note that some pagers will let you back up by means of "b". The order of this section is chosen to approximate the order in which most people prepare their input ($CONTRL, $BASIS/$DATA, $GUESS, and so on). After that comes run type related input, then properties input, input for two different solvation models, integral related input, and finally CI/MCSCF input. The next page contains a list of all possible input groups, in the order in which they can be found in this section. 1 * name function module:routine ---- -------- -------------- Molecule, basis, wavefunction specification: $CONTRL chemical control data INPUTA:START $SYSTEM computer related control data INPUTA:START $BASIS basis set INPUTB:BASISS $DATA molecule, basis set INPUTB:MOLE $ZMAT coded z-matrix ZMATRX:ZMATIN $LIBE linear bend data ZMATRX:LIBE $SCF HF-SCF wavefunction control SCFLIB:SCFIN $SCFMI SCF-MI input control data SCFMI :MIINP $DFT density functional input DFT :DFTINP $MP2 2nd order Moller-Plesset MP2 :MP2INP $GUESS initial orbital selection GUESS :GUESMO $VEC orbitals (formatted) GUESS :READMO $MOFRZ freezes MOs during SCF runs EFPCOV:MFRZIN Potential energy surface options: $STATPT geometry search control STATPT:SETSIG $TRUDGE nongradient optimization TRUDGE:TRUINP $TRURST restart data for TRUDGE TRUDGE:TRUDGX $FORCE hessian, normal coordinates HESS :HESSX $CPHF coupled-Hartree-Fock options CPHF :CPINP $HESS force constant matrix (formatted) HESS :FCMIN $GRAD gradient vector (formatted) HESS :EGIN $DIPDR dipole deriv. matrix (formatted) HESS :DDMIN $VIB HESSIAN restart data (formatted) HESS :HSSNUM $MASS isotope selection VIBANL:RAMS $IRC intrinsic reaction path RXNCRD:IRCX $VSCF vibrational SCF and MP2 VSCF :VSCFIN $VIBSCF VSCF restart data (formatted) VSCF :VGRID $DRC dynamic reaction path DRC :DRCDRV $GLOBOP Monte Carlo global fragment opt GLOBOP:GLOPDR $GRADEX gradient extremal path GRADEX:GRXSET $SURF potential surface scan SURF :SRFINP continued on the next page... 1 * name function module:routine ---- -------- -------------- Interpretation, properties: $LOCAL orbital localization control LOCAL :LMOINP $TWOEI J,K integrals (formatted) LOCCD :TWEIIN $TRUNCN localized orbital truncations EFPCOV:TRNCIN $ELMOM electrostatic moments PRPLIB:INPELM $ELPOT electrostatic potential PRPLIB:INPELP $ELDENS electron density PRPLIB:INPELD $ELFLDG electric field/gradient PRPLIB:INPELF $POINTS property calculation points PRPLIB:INPPGS $GRID property calculation mesh PRPLIB:INPPGS $PDC MEP fitting mesh PRPLIB:INPPDC $MOLGRF orbital plots PARLEY:PLTMEM $STONE distributed multipole analysis PRPPOP:STNRD $RAMAN Raman intensity RAMAN :RAMANX $ALPDR alpha polar. der. (formatted) RAMAN :ADMIN $MOROKM Morokuma energy decomposition MOROKM:MOROIN $FFCALC finite field polarizabilities FFIELD:FFLDX $TDHF time dependent HF NLO properties TDHF :TDHFX Solvation models: $EFRAG effective fragment potentials EFINP :EFINP $FRAGNAME specific named fragment pot. EFINP :RDSTFR $FRGRPL inter-fragment repulsion EFINP :RDDFRL $PCM polarizable continuum model PCM :PCMINP $PCMCAV PCM cavity generation PCM :MAKCAV $NEWCAV PCM escaped charge cavity PCM :DISREP $IEFPCM PCM integral equation form. data PCM :IEFDAT $DISBS PCM dispersion basis set PCMDIS:ENLBS $DISREP PCM dispersion/repulsion PCMVCH:MORETS $COSGMS conductor-like screening model COSMO :COSMIN $SCRF self consistent reaction field SCRF :ZRFINP Integral and integral modification options: $ECP effective core potentials ECPLIB:ECPPAR $RELWFN relativistic correction INPUTB:RWFINP $EFIELD external electric field PRPLIB:INPEF $INTGRL format for 2e- integrals INT2A :INTIN $FMM fast multipole method QMFM :QFMMIN $TRANS integral transformation TRANS :TRFIN continued on the next page... 1 * name function module:routine ---- -------- -------------- MCSCF and CI wavefunctions, and their properties: $CIINP control over CI calculation GAMESS:WFNCI $DET determinant full CI for MCSCF ALDECI:DETINP $CIDET determinant full CI ALDECI:DETINP $GEN determinant general CI for MCSCF ALGNCI:GCIINP $CIGEN determinant general CI ALGNCI:GCIINP $GCILST general determinant list ALGNCI:GCIGEN $DRT distinct row table for MCSCF GUGDRT:ORDORB $CIDRT distinct row table for CI GUGDRT:ORDORB $MCSCF parameters for MCSCF MCSCF :MCSCF $MCQDPT multireference pert. theory MCQDPT:MQREAD $CISORT integral sorting GUGSRT:GUGSRT $GUGEM Hamiltonian matrix formation GUGEM :GUGAEM $GUGDIA Hamiltonian eigenvalues/vectors GUGDGA:GUGADG $GUGDM 1e- density matrix GUGDM :GUGADM $GUGDM2 2e- density matrix GUGDM2:GUG2DM $LAGRAN CI lagrangian matrix LAGRAN:CILGRN $TRFDM2 2e- density backtransformation TRFDM2:TRF2DM $TRANST transition moments, spin-orbit TRNSTN:TRNSTX * this column is more useful to programmers than to users. 1 $CONTRL ========================================================== $CONTRL group (optional) This is a free format group specifying global switches. SCFTYP together with MPLEVL or CITYP specifies the wavefunction. You may choose from = RHF Restricted Hartree Fock calculation (default) = UHF Unrestricted Hartree Fock calculation = ROHF Restricted open shell Hartree-Fock. (high spin, see GVB for low spin) = GVB Generalized valence bond wavefunction or OCBSE type ROHF. (needs $SCF input) = MCSCF Multiconfigurational SCF wavefunction (this requires $DET or $DRT input) = NONE indicates a single point computation, rereading a converged SCF function. This option requires that you select CITYP=GUGA, ALDET, or GENCI with only RUNTYP=ENERGY or TRANSITN and with GUESS=MOREAD. MPLEVL = chooses Moller-Plesset perturbation theory level, after the SCF. See $MP2 and $MCQDPT input groups. = 0 skips the MP computation (default) = 2 performs a second order energy correction. MP2 is implemented only for RHF, UHF, ROHF, and MCSCF wave functions. Gradients are available only for RHF, so for the others you may pick from RUNTYP=ENERGY, TRUDGE, SURFACE, or FFIELD only. 1 CITYP = chooses CI computation after the SCF, for any SCFTYP except UHF. = NONE skips the CI. (default) = GUGA runs the Unitary Group CI package, which requires $CIDRT input. Gradients are available only for RHF, so for other SCFTYPs, you may choose only RUNTYP=ENERGY, TRUDGE, SURFACE, FFIELD, TRANSITN. = ALDET runs the Ames Laboratory determinant full CI package, requiring $CIDET input. RUNTYP=ENERGY only. = GENCI runs a determinant CI program that permits arbitrary specification of the determinants, requiring $CIGEN input. RUNTYP=ENERGY only. Obviously, at most one of MPLEVL or CITYP may be chosen. Likewise, you should not mix either of these with DFT. 1 $CONTRL RUNTYP specifies the type of computation, for example at a single geometry point: = ENERGY Molecular energy. (default) = GRADIENT Molecular energy plus gradient. = HESSIAN Molecular energy plus gradient plus second derivatives, including harmonic harmonic vibrational analysis. See the $FORCE and $CPHF input groups. multiple geometry options: = OPTIMIZE Optimize the molecular geometry using analytic energy gradients. See $STATPT. = TRUDGE Non-gradient total energy minimization. See groups $TRUDGE and $TRURST. = SADPOINT Locate saddle point (transition state). See the $STATPT group. = IRC Follow intrinsic reaction coordinate. See the $IRC group. = VSCF Compute anharmonic vibrational corrections (see $VSCF) = DRC Follow dynamic reaction coordinate. See the $DRC group. = GLOBOP global optimization of effective fragment positions via Monte Carlo. See $GLOBOP. = GRADEXTR Trace gradient extremal. See the $GRADEX group. = SURFACE Scan linear cross sections of the potential energy surface. See $SURF. single geometry property options: = PROP Properties will be calculated. A $DATA deck and converged $VEC group should be input. Optionally, orbital localization can be done. See $ELPOT, etc. = RAMAN computes Raman intensities, see $RAMAN. = MOROKUMA Performs monomer energy decomposition. See the $MOROKM group. = TRANSITN Compute radiative transition moment or spin-orbit coupling. See $TRANST group. = FFIELD applies finite electric fields, most commonly to extract polarizabilities. See the $FFCALC group. = TDHF analytic computation of time dependent polarizabilities. See the $TDHF group. = MAKEFP creates an effective fragment potential. * * * * * * * * * * * * * * * * * * * * * * * * * * Note that RUNTYPs involving the energy gradient, namely GRADIENT, HESSIAN, OPTIMIZE, SADPOINT, GLOBOP, IRC, GRADEXTR, and DRC, cannot be used for any CI or MP2 computation, except when SCFTYP=RHF. * * * * * * * * * * * * * * * * * * * * * * * * * * 1 $CONTRL EXETYP = RUN Actually do the run. (default) = CHECK Wavefunction and energy will not be evaluated. This lets you speedily check input and memory requirements. See the overview section for details. = DEBUG Massive amounts of output are printed, useful only if you hate trees. = routine Maximum output is generated by the routine named. Check the source for the routines this applies to. MAXIT = Maximum number of SCF iteration cycles. Pertains only to RHF, UHF, ROHF, or GVB runs. See also MAXIT in $MCSCF. (default = 30) * * * * * * * ICHARG = Molecular charge. (default=0, neutral) MULT = Multiplicity of the electronic state = 1 singlet (default) = 2,3,... doublet, triplet, and so on. ICHARG and MULT are used directly for RHF, UHF, ROHF. For GVB, these are implicit in the $SCF input, while for MCSCF or CI, these are implicit in $DRT/$CIDRT or $DET/$CIDET input. You must still give them correctly. * * * * * * * ECP = effective core potential control. = NONE all electron calculation (default). = READ read the potentials in $ECP group. = SBKJC use Stevens, Basch, Krauss, Jasien, Cundari potentials for all heavy atoms (Li-Rn are available). = HW use Hay, Wadt potentials for all the heavy atoms (Na-Xe are available). * * * * * * * RELWFN = NONE (default) See also $RELWFN input group. = NESC normalised elimination of small component, the method of K. Dyall = RESC relativistic elimination of small component, the method of T. Nakajima and K. Hirao. 1 $CONTRL * * * the next three control molecular geometry * * * COORD = choice for molecular geometry in $DATA. = UNIQUE only the symmetry unique atoms will be given, in Cartesian coords (default). = HINT only the symmetry unique atoms will be given, in Hilderbrandt style internals. = CART Cartesian coordinates will be input. Please read the warning just below!!! = ZMT GAUSSIAN style internals will be input. = ZMTMPC MOPAC style internals will be input. = FRAGONLY means no part of the system is treated by ab initio means, hence $DATA is not given. The system is specified by $EFRAG. Note that the CART, ZMT, ZMTMPC choices require input of all atoms in the molecule. These three also orient the molecule, and then determine which atoms are unique. The reorientation is very likely to change the order of the atoms from what you input. When the point group contains a 3-fold or higher rotation axis, the degenerate moments of inertia often cause problems choosing correct symmetry unique axes, in which case you must use COORD=UNIQUE rather than Z-matrices. Warning: The reorientation into principal axes is done only for atomic coordinates, and is not applied to the axis dependent data in the following groups: $VEC, $HESS, $GRAD, $DIPDR, $VIB, nor Cartesian coords of effective fragments in $EFRAG. COORD=UNIQUE avoids reorientation, and thus is the safest way to read these. Note that the choices CART, ZMT, ZMTMPC require the use of a $BASIS group to define the basis set. The first two choices might or might not use $BASIS, as you wish. UNITS = distance units, any angles must be in degrees. = ANGS Angstroms (default) = BOHR Bohr atomic units NZVAR = 0 Use Cartesian coordinates (default). = M If COORD=ZMT or ZMTMPC and a $ZMAT is not given: the internal coordinates will be those defining the molecule in $DATA. In this case, $DATA must not contain any dummy atoms. M is usually 3N-6, or 3N-5 for linear. = M For other COORD choices, or if $ZMAT is given: the internal coordinates will be those defined in $ZMAT. This allows more sophisticated internal coordinate choices. M is ordinarily 3N-6 (3N-5), unless $ZMAT has linear bends. NZVAR refers mainly to the coordinates used by OPTIMIZE or SADPOINT runs, but may also print the internal's values for other run types. You can use internals to define the molecule, but Cartesians during optimizations! 1 $CONTRL LOCAL = controls orbital localization. = NONE Skip localization (default). = BOYS Do Foster-Boys localization. = RUEDNBRG Do Edmiston-Ruedenberg localization. = POP Do Pipek-Mezey population localization. See the $LOCAL group. Localization does not work for SCFTYP=GVB or CITYP. ISPHER = Spherical Harmonics option = -1 Use Cartesian basis functions to construct symmetry-adapted linear combination (SALC) of basis functions. The SALC space is the linear variation space used. (default) = 0 Use spherical harmonic functions to create SALC functions, which are then expressed in terms of Cartesian functions. The contaminants are not dropped, hence this option has EXACTLY the same variational space as ISPHER=-1. The only benefit to obtain from this is a population analysis in terms of pure s,p,d,f,g functions. = +1 Same as ISPHER=0, but the function space is truncated to eliminate all contaminant Cartesian functions [3S(D), 3P(F), 4S(G), and 3D(G)] before constructing the SALC functions. The computation corresponds to the use of a spherical harmonic basis. QMTTOL = linear dependence threshhold Any functions in the SALC variational space whose eigenvalue of the overlap matrix is below this tolerence is considered to be linearly dependent. Such functions are dropped from the variational space. What is dropped is not individual basis functions, but rather some linear combination(s) of the entire basis set that represent the linear dependent part of the function space. The default is a reasonable value for most purposes, 1.0E-6. When many diffuse functions are used, it is common to see the program drop some combinations. On occasion, in multi-ring molecules, we have raised QMTTOL to 3.0E-6 to obtain SCF convergence, at the cost of some energy. 1 $CONTRL * * * interfaces to other programs * * * MOLPLT = flag that produces an input deck for a molecule drawing program distributed with GAMESS. (default is .FALSE.) PLTORB = flag that produces an input deck for an orbital plotting program distributed with GAMESS. (default is .FALSE.) AIMPAC = flag to create an input deck for Bader's atoms in molecules properties code. (default=.FALSE.) For information about this program, see the URL http://www.chemistry.mcmaster.ca/aimpac FRIEND = string to prepare input to other quantum programs, choose from = HONDO for HONDO 8.2 = MELDF for MELDF = GAMESSUK for GAMESS (UK Daresbury version) = GAUSSIAN for Gaussian 9x = ALL for all of the above PLTORB, MOLPLT, and AIMPAC decks are written to file PUNCH at the end of the job. Thus all of these correspond to the final geometry encountered during jobs such as OPTIMIZE, SAPDOINT, IRC... In contrast, selecting FRIEND turns the job into a CHECK run only, no matter how you set EXETYP. Thus the geometry is that encountered in $DATA. The input is added to the PUNCH file, and may require some (usually minimal) massaging. PLTORB and MOLPLT are written even for EXETYP=CHECK. AIMPAC requires at least RUNTYP=PROP. The NBO program of Frank Weinhold's group can be attached to GAMESS. The input to control the natural bond order analysis is read by the add in code, so is not described here. The NBO program is available by anonymous FTP to ftp.osc.edu, in the directory pub/chemistry/software/SOURCES/FORTRAN/nbo 1 $CONTRL * * * computation control switches * * * For the most part, the default is the only sensible value, and unless you are sure of what you are doing, these probably should not be touched. NPRINT = Print/punch control flag See also EXETYP for debug info. (options -7 to 5 are primarily debug) = -7 Extra printing from Boys localization. = -6 debug for geometry searches = -5 minimal output = -4 print 2e-contribution to gradient. = -3 print 1e-contribution to gradient. = -2 normal printing, no punch file = 1 extra printing for basis,symmetry,ZMAT = 2 extra printing for MO guess routines = 3 print out property and 1e- integrals = 4 print out 2e- integrals = 5 print out SCF data for each cycle. (Fock and density matrices, current MOs = 6 same as 7, but wider 132 columns output. This option isn't perfect. = 7 normal printing and punching (default) = 8 more printout than 7. The extra output is (AO) Mulliken and overlap population analysis, eigenvalues, Lagrangians, ... = 9 everything in 8 plus Lowdin population analysis, final density matrix. NOSYM = 0 the symmetry specified in $DATA is used as much as possible in integrals, SCF, gradients, etc. (this is the default) = 1 the symmetry specified in the $DATA group is used to build the molecule, then symmetry is not used again. Some GVB or MCSCF runs (those without a totally symmetric charge density) require you request no symmetry. INTTYP = POPLE use fast Pople-Hehre routines for sp integral blocks, and HONDO Rys polynomial code for all other integrals. (default) = HONDO use HONDO/Rys integrals for all integrals. This option produces slightly more accurate integrals but is also slower. When diffuse functions are used, the inaccuracy in Pople/Hehre sp integrals shows up as inaccurate LCAO coefficients in virtual orbitals. This means the error in SCF (meaning RHF to MCSCF) energies is expected to be about 5d-8 Hartree, but the error in computations that OCCUPY the virtual orbitals may be much larger. We have seen an energy error of 1d-4 in an MP2 energy when diffuse functions were used. We recommend that all MP2 or CI jobs with diffuse functions select INTTYP=HONDO. 1 NORMF = 0 normalize the basis functions (default) = 1 no normalization NORMP = 0 input contraction coefficients refer to normalized Gaussian primitives. (default) = 1 the opposite. $CONTRL ITOL = primitive cutoff factor (default=20) = n products of primitives whose exponential factor is less than 10**(-n) are skipped. ICUT = n integrals less than 10.0**(-n) are not saved on disk. (default = 9) * * * restart options * * * IREST = restart control options (for OPTIMIZE run restarts, see $STATPT) Note that this option is unreliable! = -1 reuse dictionary file from previous run, useful with GEOM=DAF and/or GUESS=MOSAVED. Otherwise, this option is the same as 0. = 0 normal run (default) = 1 2e restart (1-e integrals and MOs saved) = 2 SCF restart (1-,2-e integrls and MOs saved) = 3 1e gradient restart = 4 2e gradient restart GEOM = select where to obtain molecular geometry = INPUT from $DATA input (default for IREST=0) = DAF read from DICTNRY file (default otherwise) As noted in the first chapter, binary file restart is not a well tested option! ========================================================== 1 $SYSTEM ========================================================== $SYSTEM group (optional) This group provides global control information for your computer's operation. This is system related input, and will not seem particularly chemical to you! TIMLIM = time limit, in minutes. Set to about 95 percent of the time limit given to the batch job so that GAMESS can stop itself gently. (default=600.0) MWORDS = the maximum replicated memory which your job can use, on every node. This is given in units of 1,000,000 words (as opposed to 1024*1024 words), where a word is always a 64 bit quantity. Most systems allocate this memory at run time, but some more primitive systems may have an upper limit chosen at compile time. (default=1) In case finer control over the memory is needed, this value can be given in units of words by using the keyword MEMORY instead of MWORDS. MEMDDI = the grand total memory needed for the distributed data interface (DDI) storage, given in units of 1,000,000 words. See Chapter 5 of this manual for an extended explanation of running with MEMDDI. note: the memory required on each node for a run using p processors is therefore MWORDS + MEMDDI/p. PARALL = a flag to cause the distributed data parallel MP2 program to execute the parallel algorithm even if you are running on only one node. The main purpose of this is to allow you to do EXETYP=CHECK runs to learn what the correct value of MEMDDI needs to be. KDIAG = diagonalization control switch = 0 use a vectorized diagonalization routine if one is available on your machine, else use EVVRSP. (default) = 1 use EVVRSP diagonalization. This may be more accurate than KDIAG=0. = 2 use GIVEIS diagonalization (not as fast or reliable as EVVRSP) = 3 use JACOBI diagonalization (this is the slowest method) 1 COREFL = a flag to indicate whether or not GAMESS should produce a "core" file for debugging when subroutine ABRT is called to kill a job. This variable pertains only to UNIX operating systems. (default=.FALSE.) * * * the next three refer to parallel GAMESS * * * The next three apply only to parallel runs, and as they are more or less obsolete, their use is discourged. BALTYP = Parallel load balence scheme LOOP turns off dynamic load balancing (DLB) NXTVAL uses dynamic load balancing (default = LOOP) XDR = a flag to indicate whether or not messages should be converted into a generic format known as external data representation. If true, messages can exchange between machines of different vendors, at the cost of performing the data type conversions. (default=.FALSE.) --inactive at present-- PTIME = a logical flag to print extra timing info during parallel runs. This is not currently implemented. ========================================================== 1 $BASIS ========================================================== $BASIS group (optional) This group allows certain standard basis sets to be easily given. If this group is omitted, the basis set must be given instead in the $DATA group. GBASIS = Name of the Gaussian basis set. = MINI - Huzinaga's 3 gaussian minimal basis set. Available H-Rn. = MIDI - Huzinaga's 21 split valence basis set. Available H-Rn. = STO - Pople's STO-NG minimal basis set. Available H-Xe, for NGAUSS=2,3,4,5,6. = N21 - Pople's N-21G split valence basis set. Available H-Xe, for NGAUSS=3. Available H-Ar, for NGAUSS=6. = N31 - Pople's N-31G split valence basis set. Available H-Ne,P-Cl for NGAUSS=4. Available H-He,C-F for NGAUSS=5. Available H-Ar, for NGAUSS=6. For Ga-Kr, N31 selects the BC basis. = N311 - Pople's "triple split" N-311G basis set. Available H-Ne, for NGAUSS=6. Selecting N311 implies MC for Na-Ar. = DZV - "double zeta valence" basis set. a synonym for DH for H,Li,Be-Ne,Al-Cl. (14s,9p,3d)/[5s,3p,1d] for K-Ca. (14s,11p,5d/[6s,4p,1d] for Ga-Kr. = DH - Dunning/Hay "double zeta" basis set. (3s)/[2s] for H. (9s,4p)/[3s,2p] for Li. (9s,5p)/[3s,2p] for Be-Ne. (11s,7p)/[6s,4p] for Al-Cl. = TZV - "triple zeta valence" basis set. (5s)/[3s] for H. (10s,3p)/[4s,3p] for Li. (10s,6p)/[5s,3p] for Be-Ne. a synonym for MC for Na-Ar. (14s,9p)/[8s,4p] for K-Ca. (14s,11p,6d)/[10s,8p,3d] for Sc-Zn. = MC - McLean/Chandler "triple split" basis. (12s,9p)/[6s,5p] for Na-Ar. Selecting MC implies 6-311G for H-Ne. additional values for GBASIS are on the next page. 1 * * * the next two are ECP bases only * * * GBASIS = SBKJC- Stevens/Basch/Krauss/Jasien/Cundari valence basis set, for Li-Rn. This choice implies an unscaled -31G basis for H-He. = HW - Hay/Wadt valence basis. This is a -21 split, available Na-Xe, except for the transition metals. This implies a 3-21G basis for H-Ne. * * * semiempirical basis sets * * * The elements for which these exist can be found in the 'further information' section of this manual. If you pick one of these, all other data in this group is ignored. Semi-empirical runs actually use valence-only STO bases, not GTOs. GBASIS = MNDO - selects MNDO model hamiltonian = AM1 - selects AM1 model hamiltonian = PM3 - selects PM3 model hamiltonian NGAUSS = the number of Gaussians (N). This parameter pertains only to GBASIS=STO, N21, N31, or N311. NDFUNC = number of heavy atom polarization functions to be used. These are usually d functions, except for MINI/MIDI. The term "heavy" means Na on up when GBASIS=STO, HW, or N21, and from Li on up otherwise. The value may not exceed 3. The variable POLAR selects the actual exponents to be used, see also SPLIT2 and SPLIT3. (default=0) NFFUNC = number of heavy atom f type polarization functions to be used on Li-Cl. This may only be input as 0 or 1. (default=0) NPFUNC = number of light atom, p type polarization functions to be used on H-He. This may not exceed 3, see also POLAR. (default=0) DIFFSP = flag to add diffuse sp (L) shell to heavy atoms. Heavy means Li-F, Na-Cl, Ga-Br, In-I, Tl-At. The default is .FALSE. DIFFS = flag to add diffuse s shell to hydrogens. The default is .FALSE. Warning: if you use diffuse functions, please read QMTTOL and INTTYP in the $CONTRL group for numerical concerns. 1 $BASIS POLAR = exponent of polarization functions = POPLE (default for all other cases) = POPN311 (default for GBASIS=N311, MC) = DUNNING (default for GBASIS=DH, DZV) = HUZINAGA (default for GBASIS=MINI, MIDI) = HONDO7 (default for GBASIS=TZV) SPLIT2 = an array of splitting factors used when NDFUNC or NPFUNC is 2. Default=2.0,0.5 SPLIT3 = an array of splitting factors used when NDFUNC or NPFUNC is 3. Default=4.00,1.00,0.25 EXTFIL = a flag to read basis sets from an external file, defined by EXTBAS, instead of $DATA. No external file is provided with GAMESS, instead you would supply your own. The GBASIS keyword must give an 8 character string, obviously not using any internally stored names. Every atom must be defined in the external file by a line giving the chemical symbol, and this string. Following this header line, give the basis in free format $DATA style, containing only S, P, D, F, G, and L shells, and terminating each atom by the usual blank line. The GBASIS string allows you to have several families of bases in the same file, identified by different strings. (default=.false.) ========================================================== The splitting factors are from the Pople school, and are probably too far apart. See for example the Binning and Curtiss paper. For example, the SPLIT2 value will usually cause an INCREASE over the 1d energy at the HF level for hydrocarbons. The actual exponents used for polarization functions, as well as for diffuse sp or s shells, are described in the 'Further References' section of this manual. This section also describes the sp part of the basis set chosen by GBASIS fully, with all references cited. Note that GAMESS always punches a full $DATA group. Thus, if $BASIS does not quite cover the basis you want, you can obtain this full $DATA group from EXETYP=CHECK, and then change polarization exponents, add Rydbergs, etc. 1 $DATA ========================================================== $DATA group (required) $DATAS group (if NESC chosen, gives small component basis) $DATAL group (if NESC chosen, gives large component basis) This group describes the global molecular data such as point group symmetry, nuclear coordinates, and possibly the basis set. It consists of a series of free format card images. See $RELWFN for more information on large and small component basis sets. The input structure of $DATAS and $DATAL is identical to the COORD=UNIQUE $DATA input. ---------------------------------------------------------- -1- TITLE a single descriptive title card. ---------------------------------------------------------- -2- GROUP, NAXIS GROUP is the Schoenflies symbol of the symmetry group, you may choose from C1, Cs, Ci, Cn, S2n, Cnh, Cnv, Dn, Dnh, Dnd, T, Th, Td, O, Oh. NAXIS is the order of the highest rotation axis, and must be given when the name of the group contains an N. For example, "Cnv 2" is C2v. "S2n 3" means S6. Use of NAXIS up to 8 is supported in each axial groups. For linear molecules, choose either Cnv or Dnh, and enter NAXIS as 4. Enter atoms as Dnh with NAXIS=2. If the electronic state of either is degenerate, check the note about the effect of symmetry in the electronic state in the SCF section of REFS.DOC. ---------------------------------------------------------- In order to use GAMESS effectively, you must be able to recognize the point group name for your molecule. This presupposes a knowledge of group theory at about the level of Cotton's "Group Theory", Chapter 3. Armed with only the name of the group, GAMESS is able to exploit the molecular symmetry throughout almost all of the program, and thus save a great deal of computer time. GAMESS does not require that you know very much else about group theory, although a deeper knowledge (character tables, irreducible representations, term symbols, and so on) is useful when dealing with the more sophisticated wavefunctions. 1 $DATA Cards -3- and -4- are quite complicated, and are rarely given. A *SINGLE* blank card may replace both cards -3- and -4-, to select the 'master frame', which is defined on the next page. If you choose to enter a blank card, skip to the bottom of the next page. Note! If the point group is C1 (no symmetry), skip over cards -3- and -4- (which means no blank card). ---------------------------------------------------------- -3- X1, Y1, Z1, X2, Y2, Z2 For C1 group, there is no card -3- or -4-. For CI group, give one point, the center of inversion. For CS group, any two points in the symmetry plane. For axial groups, any two points on the principal axis. For tetrahedral groups, any two points on a two-fold axis. For octahedral groups, any two points on a four-fold axis. ---------------------------------------------------------- -4- X3, Y3, Z3, DIRECT third point, and a directional parameter. For CS group, one point of the symmetry plane, noncollinear with points 1 and 2. For CI group, there is no card -4-. For other groups, a generator sigma-v plane (if any) is the (x,z) plane of the local frame (CNV point groups). A generator sigma-h plane (if any) is the (x,y) plane of the local frame (CNH and dihedral groups). A generator C2 axis (if any) is the x-axis of the local frame (dihedral groups). The perpendicular to the principal axis passing through the third point defines a direction called D1. If DIRECT='PARALLEL', the x-axis of the local frame coincides with the direction D1. If DIRECT='NORMAL', the x-axis of the local frame is the common perpendicular to D1 and the principal axis, passing through the intersection point of these two lines. Thus D1 coincides in this case with the negative y axis. ---------------------------------------------------------- 1 $DATA The 'master frame' is just a standard orientation for the molecule. By default, the 'master frame' assumes that 1. z is the principal rotation axis (if any), 2. x is a perpendicular two-fold axis (if any), 3. xz is the sigma-v plane (if any), and 4. xy is the sigma-h plane (if any). Use the lowest number rule that applies to your molecule. Some examples of these rules: Ammonia (C3v): the unique H lies in the XZ plane (R1,R3). Ethane (D3d): the unique H lies in the YZ plane (R1,R2). Methane (Td): the H lies in the XYZ direction (R2). Since there is more than one 3-fold, R1 does not apply. HP=O (Cs): the mirror plane is the XY plane (R4). In general, it is a poor idea to try to reorient the molecule. Certain sections of the program, such as the orbital symmetry assignment, do not know how to deal with cases where the 'master frame' has been changed. Linear molecules (C4v or D4h) must lie along the z axis, so do not try to reorient linear molecules. You can use EXETYP=CHECK to quickly find what atoms are generated, and in what order. This is typically necessary in order to use the general $ZMAT coordinates. * * * * Depending on your choice for COORD in $CONTROL, if COORD=UNIQUE, follow card sequence U if COORD=HINT, follow card sequence U if COORD=CART, follow card sequence C if COORD=ZMT, follow card sequence G if COORD=ZMTMPC, follow card sequence M Card sequence U is the only one which allows you to define a completely general basis here in $DATA. Recall that UNIT in $CONTRL determines the distance units. 1 $DATA ---------------------------------------------------------- -5U- Atom input. Only the symmetry unique atoms are input, GAMESS will generate the symmetry equivalent atoms according to the point group selected above. if COORD=UNIQUE NAME, ZNUC, X, Y, Z *************** NAME = 10 character atomic name, used only for printout. Thus you can enter H or Hydrogen, or whatever. ZNUC = nuclear charge. It is the nuclear charge which actually defines the atom's identity. X,Y,Z = Cartesian coordinates. if COORD=HINT ************* NAME,ZNUC,CONX,R,ALPHA,BETA,SIGN,POINT1,POINT2,POINT3 NAME = 10 character atomic name (used only for print out). ZNUC = nuclear charge. CONX = connection type, choose from 'LC' linear conn. 'CCPA' central conn. 'PCC' planar central conn. with polar atom 'NPCC' non-planar central conn. 'TCT' terminal conn. 'PTC' planar terminal conn. with torsion R = connection distance. ALPHA= first connection angle BETA = second connection angle SIGN = connection sign, '+' or '-' POINT1, POINT2, POINT3 = connection points, a serial number of a previously input atom, or one of 4 standard points: O,I,J,K (origin and unit points on axes of master frame). defaults: POINT1='O', POINT2='I', POINT3='J' ref- R.L. Hilderbrandt, J.Chem.Phys. 51, 1654 (1969). You cannot understand HINT input without reading this. Note that if ZNUC is negative, the internally stored basis for ABS(ZNUC) is placed on this center, but the calculation uses ZNUC=0 after this. This is useful for basis set superposition error (BSSE) calculations. ---------------------------------------------------------- * * * If you gave $BASIS, continue entering cards -5U- until all the unique atoms have been specified. When you are done, enter a " $END " card. * * * If you did not, enter cards -6U-, -7U-, -8U-. 1 $DATA ---------------------------------------------------------- -6U- GBASIS, NGAUSS, (SCALF(i),i=1,4) GBASIS has exactly the same meaning as in $BASIS. You may choose from MINI, MIDI, STO, N21, N31, N311, DZV, DH, BC, TZV, MC, SBKJC, or HW. In addition, you may choose S, P, D, F, G, or L to enter an explicit basis set. Here, L means both an s and p shell with a shared exponent. NGAUSS is the number of Gaussians (N) in the Pople style basis, or user input general basis. It has meaning only for GBASIS=STO, N21, N31, or N311, and S,P,D,F,G, or L. Up to four scale factors may be entered. If omitted, standard values are used. They are not documented as every GBASIS treats these differently. Read the source code if you need to know more. They are seldom given. ---------------------------------------------------------- * * * If GBASIS is not S,P,D,F,G, or L, either add more shells by repeating card -6U-, or go on to -8U-. * * * If GBASIS=S,P,D,F,G, or L, enter NGAUSS cards -7U-. ---------------------------------------------------------- -7U- IG, ZETA, C1, C2 IG = a counter, IG takes values 1, 2, ..., NGAUSS. ZETA = Gaussian exponent of the IG'th primitive. C1 = Contraction coefficient for S,P,D,F,G shells, and for the s function of L shells. C2 = Contraction coefficient for the p in L shells. ---------------------------------------------------------- * * * For more shells on this atom, go back to card -6U-. * * * If there are no more shells, go on to card -8U-. ---------------------------------------------------------- -8U- A blank card ends the basis set for this atom. ---------------------------------------------------------- Continue entering atoms with -5U- through -8U- until all are given, then terminate the group with a " $END " card. --- this is the end of card sequence U --- 1 $DATA COORD=CART input: ---------------------------------------------------------- -5C- Atom input. Cartesian coordinates for all atoms must be entered. They may be arbitrarily rotated or translated, but must possess the actual point group symmetry. GAMESS will reorient the molecule into the 'master frame', and determine which atoms are the unique ones. Thus, the final order of the atoms may be different from what you enter here. NAME, ZNUC, X, Y, Z NAME = 10 character atomic name, used only for printout. Thus you can enter H or Hydrogen, or whatever. ZNUC = nuclear charge. It is the nuclear charge which actually defines the atom's identity. X,Y,Z = Cartesian coordinates. ---------------------------------------------------------- Continue entering atoms with card -5C- until all are given, and then terminate the group with a " $END " card. --- this is the end of card sequence C --- 1 $DATA COORD=ZMT input: (GAUSSIAN style internals) ---------------------------------------------------------- -5G- ATOM Only the name of the first atom is required. See -8G- for a description of this information. ---------------------------------------------------------- -6G- ATOM i1 BLENGTH Only a name and a bond distance is required for atom 2. See -8G- for a description of this information. ---------------------------------------------------------- -7G- ATOM i1 BLENGTH i2 ALPHA Only a name, distance, and angle are required for atom 3. See -8G- for a description of this information. ---------------------------------------------------------- -8G- ATOM i1 BLENGTH i2 ALPHA i3 BETA i4 ATOM is the chemical symbol of this atom. It can be followed by numbers, if desired, for example Si3. The chemical symbol implies the nuclear charge. i1 defines the connectivity of the following bond. BLENGTH is the bond length "this atom-atom i1". i2 defines the connectivity of the following angle. ALPHA is the angle "this atom-atom i1-atom i2". i3 defines the connectivity of the following angle. BETA is either the dihedral angle "this atom-atom i1- atom i2-atom i3", or perhaps a second bond angle "this atom-atom i1-atom i3". i4 defines the nature of BETA, If BETA is a dihedral angle, i4=0 (default). If BETA is a second bond angle, i4=+/-1. (sign specifies one of two possible directions). ---------------------------------------------------------- o Repeat -8G- for atoms 4, 5, ... o The use of ghost atoms is possible, by using X or BQ for the chemical symbol. Ghost atoms preclude the option of an automatic generation of $ZMAT. o The connectivity i1, i2, i3 may be given as integers, 1, 2, 3, 4, 5,... or as strings which match one of the ATOMs. In this case, numbers must be added to the ATOM strings to ensure uniqueness! 1 $DATA o In -6G- to -8G-, symbolic strings may be given in place of numeric values for BLENGTH, ALPHA, and BETA. The same string may be repeated, which is handy in enforcing symmetry. If the string is preceeded by a minus sign, the numeric value which will be used is the opposite, of course. Any mixture of numeric data and symbols may be given. If any strings were given in -6G- to -8G-, you must provide cards -9G- and -10G-, otherwise you may terminate the group now with a " $END " card. ---------------------------------------------------------- -9G- A blank line terminates the Z-matrix section. ---------------------------------------------------------- -10G- STRING VALUE STRING is a symbolic string used in the Z-matrix. VALUE is the numeric value to substitute for that string. ---------------------------------------------------------- Continue entering -10G- until all STRINGs are defined. Note that any blank card encountered while reading -10G- will be ignored. GAMESS regards all STRINGs as variables (constraints are sometimes applied in $STATPT). It is not necessary to place constraints to preserve point group symmetry, as GAMESS will never lower the symmetry from that given at -2-. When you have given all STRINGs a VALUE, terminate the group with a " $END " card. --- this is the end of card sequence G --- * * * * The documentation for sequence G above and sequence M below presumes you are reasonably familiar with the input to GAUSSIAN or MOPAC. It is probably too terse to be understood very well if you are unfamiliar with these. A good tutorial on both styles of Z-matrix input can be found in Tim Clark's book "A Handbook of Computational Chemistry", published by John Wiley & Sons, 1985. Both Z-matrix input styles must generate a molecule which possesses the symmetry you requested at -2-. If not, your job will be terminated automatically. 1 $DATA COORD=ZMTMPC input: (MOPAC style internals) ---------------------------------------------------------- -5M- ATOM Only the name of the first atom is required. See -8M- for a description of this information. ---------------------------------------------------------- -6M- ATOM BLENGTH Only a name and a bond distance is required for atom 2. See -8M- for a description of this information. ---------------------------------------------------------- -7M- ATOM BLENGTH j1 ALPHA j2 Only a bond distance from atom 2, and an angle with repect to atom 1 is required for atom 3. If you prefer to hook atom 3 to atom 1, you must give connectivity as in -8M-. See -8M- for a description of this information. ---------------------------------------------------------- -8M- ATOM BLENGTH j1 ALPHA j2 BETA j3 i1 i2 i3 ATOM, BLENGTH, ALPHA, BETA, i1, i2 and i3 are as described at -8G-. However, BLENGTH, ALPHA, and BETA must be given as numerical values only. In addition, BETA is always a dihedral angle. i1, i2, i3 must be integers only. The j1, j2 and j3 integers, used in MOPAC to signal optimization of parameters, must be supplied but are ignored here. You may give them as 0, for example. ---------------------------------------------------------- Continue entering atoms 3, 4, 5, ... with -8M- cards until all are given, and then terminate the group by giving a " $END " card. --- this is the end of card sequence M --- ========================================================== This is the end of $DATA! If you have any doubt about what molecule and basis set you are defining, or what order the atoms will be generated in, simply execute an EXETYP=CHECK job to find out! 1 $ZMAT ========================================================== $ZMAT group (required if NZVAR is nonzero in $CONTRL) This group lets you define the internal coordinates in which the gradient geometry search is carried out. These need not be the same as the internal coordinates used in $DATA. The coordinates may be simple Z-matrix types, delocalized coordinates, or natural internal coordinates. You must input a total of M=3N-6 internal coordinates (M=3N-5 for linear molecules). NZVAR in $CONTRL can be less than M IF AND ONLY IF you are using linear bends. It is also possible to input more than M coordinates if they are used to form exactly M linear combinations for new internals. These may be symmetry coordinates or natural internal coordinates. If NZVAR > M, you must input IJS and SIJ below to form M new coordinates. See DECOMP in $FORCE for the only circumstance in which you may enter a larger NZVAR without giving SIJ and IJS. **** IZMAT defines simple internal coordinates **** IZMAT is an array of integers defining each coordinate. The general form for each internal coordinate is code number,I,J,K,L,M,N IZMAT =1 followed by two atom numbers. (I-J bond length) =2 followed by three numbers. (I-J-K bond angle) =3 followed by four numbers. (dihedral angle) Torsion angle between planes I-J-K and J-K-L. =4 followed by four atom numbers. (atom-plane) Out-of-plane angle from bond I-J to plane J-K-L. =5 followed by three numbers. (I-J-K linear bend) Counts as 2 coordinates for the degenerate bend, normally J is the center atom. See $LIBE. =6 followed by five atom numbers. (dihedral angle) Dihedral angle between planes I-J-K and K-L-M. =7 followed by six atom numbers. (ghost torsion) Let A be the midpoint between atoms I and J, and B be the midpoint between atoms M and N. This coordinate is the dihedral angle A-K-L-B. The atoms I,J and/or M,N may be the same atom number. (If I=J AND M=N, this is a conventional torsion). Examples: N2H4, or, with one common pair, H2POH. Example - a nonlinear triatomic, atom 2 in the middle: $ZMAT IZMAT(1)=1,1,2, 2,1,2,3, 1,2,3 $END This sets up two bonds and the angle between them. The blanks between each coordinate definition are not necessary, but improve readability mightily. 1 $ZMAT **** the next define delocalized coordinates **** DLC is a flag to request delocalized coordinates. (default is .FALSE.) AUTO is a flag to generate all redundant coordinates, automatically. The DLC space will consist of all non-redundant combinations of these which can be found. The list of redundant coordinates will consist of bonds, angles, and torsions only. (default is .FALSE.) NONVDW is an array of atom pairs which are to be joined by a bond, but might be skipped by the routine that automatically includes all distances shorter than the sum of van der Waals radii. Any angles and torsions associated with the new bond(s) are also automatically included. The format for IXZMAT, IRZMAT, IFZMAT is that of IZMAT: IXZMAT is an extra array of simple internal coordinates which you want to have added to the list generated by AUTO. Unlike NONVDW, IXZMAT will add only the coordinate(s) you specify. IRZMAT is an array of simple internal coordinates which you would like to remove from the AUTO list of redundant coordinates. It is sometimes necessary to remove a torsion if other torsions around a bond are being frozen, to obtain a nonsingular G matrix. IFZMAT is an array of simple internal coordinates which you would like to freeze. See also FVALUE below. Note that IFZMAT/FVALUE work only with DLC, see the IFREEZ option in $STATPT to freeze coordinates if you wish to freeze simple or natural coordinates. FVALUE is an array of values to which the internal coordinates should be constrained. It is not necessary to input $DATA such that the initial values match these desired final values, but it is helpful if the initial values are not too far away. 1 $ZMAT $LIBE **** SIJ,IJS define natural internal coordinates **** SIJ is a transformation matrix of dimension NZVAR x M, used to transform the NZVAR internal coordinates in IZMAT into M new internal coordinates. SIJ is a sparse matrix, so only the non-zero elements are given, by using the IJS array described below. The columns of SIJ will be normalized by GAMESS. (Default: SIJ = I, unit matrix) IJS is an array of pairs of indices, giving the row and column index of the entries in SIJ. example - if the above triatomic is water, using IJS(1) = 1,1, 3,1, 1,2, 3,2, 2,3 SIJ(1) = 1.0, 1.0, 1.0,-1.0, 1.0 gives the matrix S= 1.0 1.0 0.0 0.0 0.0 1.0 1.0 -1.0 0.0 which defines the symmetric stretch, asymmetric stretch, and bend of water. references for natural internal coordinates: P.Pulay, G.Fogarasi, F.Pang, J.E.Boggs J.Am.Chem.Soc. 101, 2550-2560(1979) G.Fogarasi, X.Zhou, P.W.Taylor, P.Pulay J.Am.Chem.Soc. 114, 8191-8201(1992) reference for delocalized coordinates: J.Baker, A. Kessi, B.Delley J.Chem.Phys. 105, 192-212(1996) ========================================================== $LIBE group (required if linear bends are used in $ZMAT) A degenerate linear bend occurs in two orthogonal planes, which are specified with the help of a point A. The first bend occurs in a plane containing the atoms I,J,K and the user input point A. The second bend is in the plane perpendicular to this, and containing I,J,K. One such point must be given for each pair of bends used. APTS(1)= x1,y1,z1,x2,y2,z2,... for linear bends 1,2,... Note that each linear bend serves as two coordinates, so that if you enter 2 linear bends (HCCH, for example), the correct value of NZVAR is M-2, where M=3N-6 or 3N-5, as appropriate. ========================================================== 1 $SCF ========================================================== $SCF group relevant if SCFTYP = RHF, UHF, or ROHF, required if SCFTYP = GVB) This group of parameters provides additional control over the RHF, UHF, ROHF, or GVB SCF steps. It must be used for GVB open shell or perfect pairing wavefunctions. DIRSCF = a flag to activate a direct SCF calculation, which is implemented for all the Hartree-Fock type wavefunctions: RHF, ROHF, UHF, and GVB. This keyword also selects direct MP2 computation. The default of .FALSE. stores integrals on disk storage for a conventional SCF calculation. FDIFF = a flag to compute only the change in the Fock matrices since the previous iteration, rather than recomputing all two electron contributions. This saves much CPU time in the later iterations. This pertains only to direct SCF, and has a default of .TRUE. This option is implemented only for the RHF, ROHF, UHF cases. Cases with many diffuse functions in the basis set sometimes oscillate at the end, rather than converging. Turning this parameter off will normally give convergence. ---- The next flags affect convergence rates. EXTRAP = controls Pople extrapolation of the Fock matrix. DAMP = controls Davidson damping of the Fock matrix. SHIFT = controls level shifting of the Fock matrix. RSTRCT = controls restriction of orbital interchanges. DIIS = controls Pulay's DIIS interpolation. SOSCF = controls second order SCF orbital optimization. (default=.TRUE. for RHF, Abelian group ROHF, GVB) (default=.FALSE. for UHF, non-Abelian group ROHF) DEM = controls direct energy minimization, which is implemented only for RHF. (default=.FALSE.) defaults for EXTRAP DAMP SHIFT RSTRCT DIIS SOSCF ab initio: T F F F T T/F semiempirical: T F F F F F The above parameters are implemented for all SCF wavefunction types, except that DIIS will work for GVB only for those cases with NPAIR=0 or NPAIR=1. If both DIIS and SOSCF are chosen, SOSCF is stronger than DIIS, and so DIIS will not be used. Once either DIIS or SOSCF are initiated, any other accelerator in effect is put in abeyance. 1 $SCF ---- These parameters fine tune the various convergers. CONV = SCF density convergence criteria. Convergence is reached when the density change between two consecutive SCF cycles is less than this in absolute value. One more cycle will be executed after reaching convergence. Less accuracy in CONV gives questionable gradients. The default is 1.0d-05, except runs involving CI or MP2 gradients use 1.0d-06. SOGTOL = second order gradient tolerance. SOSCF will be initiated when the orbital gradient falls below this threshold. (default=0.25 au) ETHRSH = energy error threshold for initiating DIIS. The DIIS error is the largest element of e=FDS-SDF. Increasing ETHRSH forces DIIS on sooner. (default = 0.5 Hartree) MAXDII = Maximum size of the DIIS linear equations, so that at most MAXDII-1 Fock matrices are used in the interpolation. (default=10) DEMCUT = Direct energy minimization will not be done once the density matrix change falls below this threshold. (Default=0.5) DMPCUT = Damping factor lower bound cutoff. The damping damping factor will not be allowed to drop below this value. (default=0.0) note: The damping factor need not be zero to achieve valid convergence (see Hsu, Davidson, and Pitzer, J.Chem.Phys., 65, 609 (1976), see especially the section on convergence control), but it should not be astronomical either. * * * * * * * * * * * * * * * * * * * * * For more info on the convergence methods, see the 'Further Information' section. * * * * * * * * * * * * * * * * * * * * * 1 ----- miscellaneous options ----- UHFNOS = flag controlling generation of the natural orbitals of a UHF function. (default=.FALSE.) MVOQ = 0 Skip MVO generation (default) = n Form modified virtual orbitals, using a cation with n electrons removed. Implemented for RHF, ROHF, and GVB. If necessary to reach a closed shell cation, the program might remove n+1 electrons. Typically, n will be about 6. = -1 The cation used will have each valence orbital half filled, to produce MVOs with valence-like character in all regions of the molecule. Implemented for RHF and ROHF only. NPUNCH = SCF punch option = 0 do not punch out the final orbitals = 1 punch out the occupied orbitals = 2 punch out occupied and virtual orbitals The default is NPUNCH = 2. ----- options for virial scaling ----- VTSCAL = A flag to request that the virial theorem be satisfied. An analysis of the total energy as an exact sum of orbital kinetic energies is printed. The default is .FALSE. This option is implemented for RHF, UHF, and ROHF, for RUNTYP=ENERGY, OPTIMIZE, or SADPOINT. Related input is as follows: SCALF = initial exponent scale factor when VTSCAL is in use, useful when restarting. The default is 1.0. MAXVT = maximum number of iterations (at a single geometry) to satisfy the energy virial theorem. The default is 20. VTCONV = convergence criterion for the VT, which is satisfied when 2 + + R x dE/dR is less than VTCONV. The default is 1.0D-6 Hartree. For more information on this option, which is most economically employed during a geometry search, see M.Lehd and F.Jensen, J.Comput.Chem. 12, 1089-1096(1991). 1 $SCF The next parameters define the GVB wavefunction. Note that ALPHA and BETA also have meaning for ROHF. See also MULT in the $CONTRL group. The GVB wavefunction assumes orbitals are in the order core, open, pairs. NCO = The number of closed shell orbitals. The default almost certainly should be changed! (default=0). NSETO = The number of sets of open shells in the function. Maximum of 10. (default=0) NO = An array giving the degeneracy of each open shell set. Give NSETO values. (default=0,0,0,...). NPAIR = The number of geminal pairs in the -GVB- function. Maximum of 12. The default corresponds to open shell SCF (default=0). CICOEF = An array of ordered pairs of CI coefficients for the -GVB- pairs. For example, a two pair case for water, say, might be CICOEF(1)=0.95,-0.05,0.95,-0.05. If not normalized, as in the default, they will be. This parameter is useful in restarting a GVB run, with the current CI coefficients. (default = 0.90,-0.20,0.90,-0.20,...) COUPLE = A switch controlling the input of F, ALPHA, and BETA. The default is to use internally stored values for these variables. Note ALPHA and BETA can be given for -ROHF-, as well as -GVB-. (Default=.FALSE.) F = An vector of fractional occupations. ALPHA = An array of A coupling coefficients given in lower triangular order. BETA = An array of B coupling coefficients given in lower triangular order. Note: The default for F, ALPHA, and BETA depends on the state chosen. Defaults for the most commonly occuring cases are internally stored. * * * * * * * * * * * * * * * * * * * For more discussion of GVB/ROHF input see the 'further information' section * * * * * * * * * * * * * * * * * * * ========================================================== 1 $SCFMI ========================================================== $SCFMI group (optional, relevant if SCFTYP=RHF) The SCF-MI method is a modification of the Roothaan equations that avoids basis set superposition error (BSSE) in intermolecular interaction calculations, by expanding each monomer's orbitals using only its own basis set. Thus, the resulting orbitals are not orthogonal. The presence of a $SCFMI group in the input triggers the use of this option. The implementation is limited to two monomers, treated at the RHF level. The energy, gradient, and therefore numerical hessian are available. The SCF step may be run in direct SCF mode. The first 4 parameters must be given. All atoms of monomer A must be given in $DATA before the atoms of monomer B. NA = number of doubly occupied MOs on fragment A. NB = number of doubly occupied MOs on fragment B. MA = number of basis functions on fragment A. MB = number of basis functions on fragment B. ITER = maximum number of SCF-MI cycles, overriding the usual MAXIT value. (default is 50). DTOL = SCF-MI density convergence criteria. (default is 1.0d-10) ALPHA = possible level shift parameter. (default is 0.0, meaning shifting is not used) IOPT = prints additional debug information. = 0 standard outout (default) = 1 print for each SCF-MI cycle MOs, overlap between the MOs, CPU times. = 2 print some extra informations in secular systems solution. MSHIFT = debugging option that permits to shift all the memory pointer of the SCF-MI section of code of the quantity MSHIFT (default is 0). ========================================================== "Modification of Roothan Equations to Exclude BSSE from Molecular Interaction Calculations" E. Gianinetti, M. Raimondi, E. Tornaghi Int. J. Quantum Chem. 60, 157 (1996) A. Famulari, E. Gianinetti, M. Raimondi, and M. Sironi Int. J. Quantum Chem. (1997), submitted. 1 $DFT ========================================================== $DFT group (relevant if SCFTYP=RHF,UHF,ROHF) Note that if DFTTYP=NONE, an ab initio calculation will be performed, rather than density functional theory. This group permits the use of various one electron (usually empirical) operators instead of the true many electron Hamiltonian. Two programs are provided, METHOD= GRID or GRIDFREE. The programs have different functionals available, and so the keyword DFTTYP and other associated inputs are documented separately below. Every functional that has the same name in both lists is the identical functional, but each METHOD has a few functionals that are missing in the other. The grid free implementation is based on the use of the resolution of the identity to simplify integrals so that they may be analytically evaluated, without using grid quadratures. The grid free DFT computations in their present form have various numerical errors, primarily in the gradient vectors. Please do not use the grid-free DFT program without reading the discussion in the 'Further References' section regarding the gradient accuracy. The grid based DFT uses a typical grid quadrature to compute integrals over the rather complicated functionals. Achieving a self-consistent field with DFT is somewhat more difficult than for normal HF, so DIIS is the default converger. Since the DFT iterations are also more time consuming, the use of GUESS=MOREAD may be very helpful. Both DFT programs will run in parallel. 1 $DFT DFTTYP = NONE means no DFT is performed (default) METHOD = selects grid based DFT or grid free DFT. = GRID Grid based DFT (default) = GRIDFREE Grid free DFT ----- options for METHOD=GRID ----- DFTTYP = specifies exchange and correlation functionals. = SLATER Slater exchange = BECKE Becke 1988 exchange = GILL Gill 1996 exchange = PBE Perdew-Burke-Ernzerhof (PBE) exchange Note that the PBE correlation functional is not implemented. = SVWN SLATER + Vosko-Wilk-Nusair correlation, using their electron gas formula 5 (VWN5) Also known as LDA/LSDA for RHF/UHF. = SLYP SLATER + Lee-Yang-Parr (LYP) correlation = SOP SLATER + One-parameter Progressive corr. = BVWN BECKE exchange + VWN5 correlation = BLYP BECKE exchange + LYP correlation = BOP BECKE exchange + OP correlation = GVWN GILL exchange + VWN5 correlation = GLYP GILL exchange + LYP correlation = GOP GILL exchange + OP correlation = PBEVWN PBE exchange + VWN5 correlation = PBELYP PBE exchange + LYP correlation = PBEOP PBE exchange + OP correlation = HVWN Hartree-Fock exchange + VWN5 correlation = HLYP Hartree-Fock exchange + LYP correlation = HOP Hartree-Fock exchange + OP/B88 correlation = BHHLYP HF and BECKE exchange + LYP correlation = B3LYP this is a hybrid method combining five functionals, namely Becke + Slater + HF exchange and LYP + VWN5 correlation. An extensive bibliography for these functionals can be found in the 'Further References' section of this manual. 1 $DFT NRAD = number of radial grids in Euler-Maclaurin quadrature. (default=96) NTHE = number of angle theta grids in Gauss-Legendre quadrature. (default=12) NPHI = number of angle phi grids in Gauss-Legendre quadrature. NPHI should be double NTHE so that points are spherically distributed. (default=24) NRAD*NTHE*NPHI grid points will be constructed around each atom. Time is linear in the number of grid points, so be careful. Energies can be compared only when the identical grid density has been used, analogous to needing to compare with the identical basis set expansions. A very accurate "army grade" grid capable of producing an integration error less than a microHartree/atom is NRAD=96 NTHE=36 NPHI=72. NRAD0, NTHE0, NPHI0 define a smaller grid used during the SCF iterations before some initial convergence is reached. After that, the full grid defined by NRAD, NTHE, NPHI will be used. This can save considerable CPU time in the early SCF iterations. SWITCH = when the change in the density matrix between iterations falls below this threshhold, switch to use of the desired full grid (default=3.0E-4) NRAD0 = same as NRAD, but defines initial (smaller) grid. NTHE0 = same as NTHE, but defines initial (smaller) grid. NPHI0 = same as NPHI, but defines initial (smaller) grid. Default values for the initial grid depend upon NRAD, NTHE, and NPHI. For the default full grid settings, the initial grid is NRAD0=24, NTHE0=8, NPHI0=16, for other values the formula is NRAD0 the larger of NRAD/4 or 24, for NTHE0 the larger of NTHE/3 or 8, and for NPHI0 the larger of NPHI/3 or 16. In case of slow convergence of the SCF or if using the "army grade grid", NRAD0=48 NTHE0=12 NPHI0=24 and SWITCH=1.0E-4 may be better. Numerical hessian runs set the coarse grid to the same size as the full grid, by default. THRESH = threshold for ignoring small contributions to the Fock matrix. The default is designed to produce no significant energy loss, even when the grid is as good as "army grade". If for some reason you want to turn all threshhold tests off, of course requiring more CPU, enter 1.0e-15. default: 1.0e-4/Natoms/NRAD/NTHE/NPHI 1 $DFT ----- options for METHOD=GRIDFREE ----- DFTTYP = NONE means ab initio computation (default) exchange functionals: = XALPHA X-Alpha exchange (alpha=0.7) = SLATER Slater exchange (alpha=2/3) = BECKE Becke's 1988 exchange = DEPRISTO Depristo/Kress exchange = CAMA Handy et al's mods to Becke exchange = HALF 50-50 mix of Becke and HF exchange correlation functionals: = VWN Vosko/Wilke/Nusair correlation, formula 5 = PWLOC Perdew/Wang local correlation = LYP Lee/Yang/Parr correlation exchange/correlation functionals: = BVWN Becke exchange + VWN correlation = BLYP Becke exchange + LYP correlation = BPWLOC Becke exchange + Perdew/Wang correlation = B3LYP hybridized HF/Becke/LYP using VWN formula 5 = CAMB CAMA exchange + Cambridge correlation = XVWN Xalpha exchange + VWN formula 5 correlation = XPWLOC Xalpha exchange + Perdew/Wang correlation = SVWN Slater exchange + VWN correlation = SPWLOC Slater exchange + PWLOC correlation = WIGNER Wigner exchange + correlation = WS Wigner scaled exchange + correlation = WIGEXP Wigner exponential exchange + correlation AUXFUN = AUX0 uses no auxiliary basis set for resolution of the identity, limiting accuracy. = AUX3 uses the 3rd generation of RI basis sets, These are available for the elements H to Ar, but have been carefully considered for H-Ne only. (DEFAULT) THREE = a flag to use a resolution of the identity to turn four center overlap integrals into three center integrals. This can be used only if no auxiliary basis is employed. (default=.FALSE.) ========================================================== 1 $MP2 ========================================================== $MP2