Quantum Chemistry Program

Hays E F and Allen L C 1970 Mole. A system for quantum chemistry I. General description Int. J. Quantum Chem. S 3 715-25 Hehre W J, Lathan W A, Ditchfieid R, Newton M D and Popie J A 1971 Program No 236 (Bloomington, IN Quantum Chemistry Program Exchange)... 

Note MM-i- is derived from the public domain code developed by Dr. Norm an Allinger, referred to as M.M2( 1977), and distributed by the Quantum Chemistry Program Exchange (QCPE). The code for MM-t is not derived from Dr. Allin ger s present version of code, which IS trademarked MM2 . Specifically. QCMPOlO was used as a starting point Ibr HyperChem MM-t code. The code was extensively modified and extended over several years to include molecular dynamics, switching functuins for cubic stretch terms, periodic boundary conditions, superimposed restraints, a default (additional) parameter scheme, and so on. 

HyperChem s MM-t force field uses the latest MM2 (1991) parameters and atom types (provided directly by Dr. Allin ger) with the 1977 functional form [N. L. Allinger, J. Am. Chem. Soc., 99, 8127 (1977), N. L. Allinger and Y. H. Yuh, Quantum Chemistry Program... 

U. C. Singh and P. A. KoUman, Gaussian80 (UCSE), Quantum Chemistry Program Exchange, Prog. 446 QCPE Bull 2, 121 (1982) U. C. Singh and P. A. KoUman,/ Comp. Chem. 7, 718 (1986). 

J. M. Blaney, G. M. Ctippen, A. Deating, andj. S. Dixon, DGEOM, Program 590 QCPE Bull 10, (1990), avaUable from Quantum Chemistry Program Exchange, Indiana Urdversity, Bloomington, Ind. 

Source code for the early packages such as POLYATOM, HONDO and GAUS-SIAN70 are still available from the Quantum Chemistry Program Exchange, for... 

Boyd DB. Profile of computer-assisted molecular design in industry. Quantum Chemistry Program Exchange (QCPE) Bulletin 1985 5 85-91. 

Stewart HP. MOPAC A semiempirical molecular orbital program. Quantum Chemistry Program Exchange, 1983. Prog. 455. 

We now transform the eq.(22) in the same way as done for the eq.(14) we assume that the (normalised) optimum orbitals have been determined by some existing Quantum Chemistry program along with the partial waves Rn and with the potential terms J./m, and Gum- Using these quantities we then set up the equation... 

The method presented here allows, starting with trial gaussian functions, a partial analytical treatment which we have used to improve the LCAO-GTO orbitals (trial functions) essentially obtained from all ab initio quantum chemistry programs. As in r-representation, trial functions (t>i( Hp) (Eq. 21) are conveniently expressed as linear combinations of m functions Xi(P) themselves written as linear combinations of Gt gaussian functions (LCAO-GTO approximation) gta(P). 

Gausfit, M. Herman, R.E. Stanton, Quantum Chemistry Program Exchange, 11, 237, (1973)... 

Matta, C. F. FRAGDIP01 Department of Chemistry Indiana University Bloomington, 2001 Program No. QCMP201, Quantum Chemistry Program Exchange http //qcpe.chem. 

With quantum-mechanical methods, the second derivatives of the energy could be used directly for the FF and atomic polar tensors (APT) for the dipole derivatives. Both are standardly computed in most quantum-chemistry programs but for accurate results, moderately large basis sets and/or some accommodation for correlation interaction is needed. Until recently, this has restricted most ab initio studies to modest-sized molecules. 

J.P. CHANDLER, SUBROUTINE STEPIT PROGRAM 66.1, QUANTUM CHEMISTRY PROGRAM EXCHANGE, INDIANA UNIVERSITY, BLOOMINGTON INDIANA. 

Chandler, J. P. Subroutine STEPIT Program 66.1, Quantum Chemistry Program Exchange, Indiana University, Bloomington, Indiana. 

Martinez, M. R., "Estimation of Gas-Phase Thermodynamic Parameters," Quantum Chemistry Program Exchange, Program 244 (1974). 

To close on a more positive note, we observe that the computed geometry of the enzyme-dienolate complex in the vicinity of the 3-carbonyl is insensitive to the assumed dielectric constant and is in close agreement with X-ray structures of enzyme-inhibitor complexes (see Table 4.11 and Fig. 4.15). It is really quite remarkable that 4 billion years of random walk by mother nature and a few hours of optimization with a quantum chemistry program such as Gaussian (starting with the correct functional groups) lead to the same structure for the active... 

Take an N-atomic molecule with the nuclei each at their equilibrium internuclear position. Establish a Cartesian x, y, z coordinate system for each of the nuclei such that, for Xj with i = 1,.., 3N, xi is the Cartesian x displacement of nucleus 1, x2 is the Cartesian y displacement coordinate for nucleus 1, X3 is the Cartesian z displacement coordinate for nucleus 1,..., x3N is the Cartesian z displacement for nucleus N. Use of one or another quantum chemistry program yields a set of force constants I ij in Cartesian displacement coordinates... 

Quantum Chemistry Program Exchange Catalog, Chemistry Department, Indiana University, Bloomington, IN 47001. Berkert, U. Allinger, N. L. "Molecular Mechanics , ACS Monographs Washington, D. C., 1982. 

Through the addition of automated spectrum input on instrument-based computers, automated rule generation, and automatic tracing of decision rules, PAIRS has been enhanced to be an even more valuable tool for the spectroscopist. PAIRS is available for distribution from the Quantum Chemistry Program Exchange, Indiana University, Bloomington, IN 47405 (Catalog No. QCPE 497). 

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