Computer programs Gaussian 94 suite

In excerpt 3Y, the authors refer to computational results performed with the Gaussian suite of programs, a computational package used to calculate molecular ab initio or semiempirical electronic structure theory. Computational parameters (e.g., the basis set and level of theory) are included in the description. Do not worry if you do not understand the content of excerpt 3Y the language is intended for chemists with a computational or theoretical background. 

This series presents reviews of ciurent advances in computational methodologies and applications. The first chapter written by R. Cammi, B. Mennucci, and J. Tomasi provides an overview of their developments of the Polarizable Continuum Model (PCM). This approach has been particularly popularized after its implementation into the GAUSSIAN suite of programs. The authors reveal both the theoretical and numerical aspects of the PCM model. Also, promising extensions of the theory are discussed. Among the possible applications, examples concerning the evaluation of molecular-response properties and spectroscopic quantities are provided. 

A closely related approach, using the same kind of molecular cavity has been developed by Tomasi et al. (1981). In this model, the multipole expansion is replaced by a numerical computation of the electrostatic potential inside the cavity, due to the polarization of the boundary by the solute. This model also has been improved along the years. It has various versions all known under the acronym of PCM (Canc s et al. 1997) which are implemented in the Gaussian suites of programs, and a closely related model is available in the Jaguar package (Marten et al. 1996 Tannor et al. 1994). 

Several implementations of the PCM-CC theories have been presented. Caricato et al. (2010) have presented an implementation of the PCM-CC analytical gradients for the ground state of molecular solutes within the Gaussian suite of programs (Frisch et al. 2009). Cammi et al. (2010b) have presented an implementation of the PCM-CC and PCM-EOM-CC analytical derivatives methods within the framework of SAC/SACCI methods. We hope that these computational advances can be profitably used to study molecular processes in condensed phase, where both the accuracy of the QM descriptions and the influence of the environment play a critical role, as in photo-ionization processes, electronic transitions, and charge transfer reactions. 

Programs to provide MPDs now available can use single determinant wave functions from calculations produced by the Gaussian suite of programs [16] for molecules, or by Crystal-98 [17] for periodic systems. MPDs can be produced also with correlated wave functions, via a Quantum Monte Carlo program, cf. [10,15], Probabilities can be computed for multi-determinant wave functions [18], but the optimization of Q is not implemented yet. 

The most widely used ab initio approach to the correlation energy in molecular species is the mp2 theory - second-order many-body perturbation theory. This approach is available in many quantum chemistry packages, such as the well-known Gaussian suite of computer programs [50] for which the British theoretical chemist Professor Sir John Pople frs was awarded a half share of the 1998 Nobel Prize in Chemistry. mp2 is essentially a robust, black-box method which is today the most... 

All computations were carried out with the program suite PSI2.0.8, except for the MPn calculations, which were done with GAUSSIAN 9lP... 

The suites of software programs called GAUSSIAN (latest version Gaussian 03), developed and continually updated by J. A. Pople and co-workers, have made molecular computation available to a whole community of chemists, physicists and biologists without special expertise in computational chemisty (Pople shared the 1998 Nobel Prize in Chemistry). Determination of the structure of the anticancer agent taxol (Fig. 12.14) has been one of the more spectacular accomplishments of Gaussian. 

Valence bond (VB) theory may be used as an alternative to molecular orbital (MO) theory for computational organotin studies. Most MO calculations of organotin systems use Gaussian, GAMESS, or Amsterdam density functional (ADE) program suites. A variety of VB methods exist, and although VB wavefunctions are more difficult to calculate, some VB methods can also be implemented in these programs. ... 

All computations were performed at the DFT B3LYP computational level with the 6-31+G(d,p) basis set using GAUSSIAN 98 suit of programs [23]. The geometries of the thiouracils, their tautomers, and the related base pairs... 

Pople made many developments leading to the suite of Gaussian computer oodes that now constitute the most widely used eleotronlc structure ccmputer programs... 

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