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500. GAUSSIAN 80: IBM Version II
by C. K. Foley and D. B. Chesnut, P. M. Gross Chemical Laboratory, Duke University, Durham, North Carolina 27706 after P. N. van Kampen, F.A.A.M. de Leeuw, G. F. Smits and C. Altona, Department of Chemistry, State University of Leiden, The Netherlands (IBM Verson I), an expansion of work done by J. A. Pople et al. This is an updating of QCPE 437 which corrects all known errors and avoids system-related problems which were experienced by several users in the U.S. and Canada. GAUSSIAN 80 is a connected system of programs capable of performing Ab Initio molecular orbital (MO) calculations within the linear combination of atomic orbitals (LCAO) framework. GAUSSIAN 80 is a connected system of programs for the calculation of the one- and two-electron integrals using basis sets of s, p or d Cartesian Gaussian functions.These are followed by programs for determination of Hartree-Fock (HF) single determinant wave functions and associated total energies. For closed-shell singlet states, the restricted Hartree- Fock (RHF) procedure of Roothaan is used. For open- shell states, wave functions and energies are obtained with the restricted open-shell method (ROHF). This is followed by a program for Mulliken population analysis and calculation of the electric dipole moment and spin densities at the nuclear coordinates. Further programs compute the first derivatives of the Hartree-Fock energy with respect to all nuclear coordinates. Control programs are also provided for automatic energy minimization and to find stationary points on the potential surfaces. There are several methods available for going beyond the Hartree-Fock level. The electron correlation energy may be calculated by MO(o,/)ller-Plesset perturbation theory, carried to second order (MP2) or third order (MP3). Configuration interaction calculations with all double substitutions (CID) from the Hartree-Fock reference determinant are also possible. List of programs in GAUSSIAN 80: _______________________________________________________ _______________ Link Function _______________________________________________________ _______________ Main Initialization, controls overlaying. L1 Reads route, initializes disc files, fills error-function interpolation table. L101 Reads: Title Z-matrix Variables Constants L102 Controls "Fletcher-Powell" optimization. L103 Controls "Berny" optimization. L105 Controls "Murtaugh-Sargent" optimization. L202 Calculates coordinates from Z-matrix and determines: Stoichiometry Framework group Symmetry information Rotates molecule to standard (center-of-charge) orientation. L301 Fills in basis set information. L302 Computes overlap, kinetic and potential integrals. L303 Computes x-, y- and z-dipole integrals. L305 Setup for pseudo-potential integrals. L306 Computes pseudo-potential integrals. L310 Primitive 2-electron integral program (spdf). For testing purposes only. L311 sp 2-electron integral program. L314 (sp) d 2-electron integral program. L401 Initial guess at density matrix. L501 RHF closed-shell SCF. L502 UHF open-shell SCF. L504 Direct minimization SCF (does RHF/UHF, real/complex). L505 Restricted open-shell SCF program. L601 Mulliken population analysis; Fermi contact analysis for open-shell systems; computes dipole moment. L701 Calculates one-electron integral first derivatives. L702 Calculates two-electron integral first derivatives. L703 Calculates two-electron integral first derivatives for spd functions. L705 Calculates pseudo-potential first derivative integrals for sp bases. L716 Converts forces to internal coordinate forces and communicates with optimization-control programs. L801 Setup program for transformation of two- electron integrals; produces molecular orbital coefficient matrix and eigenvalues, removing the orbitals that are not used in the correlation study. L802 RHF closed-shell transformation of two- electron integrals. L803 UHF open-shell transformation of two-electron integrals. L901 Computes anti-symmetrizedtwo-electron integrals; computes MP2 energy and MO(í)ller- Plesset first-order wave function. L909 Initialization for CID and higher-order energy perturbation calculations. L910-912 Carries out higher-order perturbation calculations or one CID iteration. L913 Calculates various energies. In the case of a CID calculation, L913 tests for convergence and, if necessary, returns to L910 for the state of the next iteration. L999 Terminates the run. _______________________________________________________ _______________ Some limitations occur throughout the Gaussian system in the form of fixed dimension statements, algorithm design limitations, etc., and their overall effect is to restrict the size of the calculation that can be performed. The limits described here are the upper limits of the most restricted parts of GAUSSIAN 80. Some parts of the program are already dimensioned to a higher limit, either for some specific calculations or for future expansions. Number of atoms 50 Number of basis functions 127 (RHF) Number of basis functions 70 (UHF, ROHF, post- SCF) The (overlayed) program requires 1Mb of (virtual) core. NOTE: Because of the size of this system, QCPE 500 will always be distributed on its own tape. IBM FORTRAN IV Lines of Code: 60,000 |