AMSOL program

One very popular technique is an adaptation of the Born model for orbital-based calculations by Cramer and Truhlar, et. al. Their solvation methods (denoted SMI, SM2, and so on) are designed for use with the semiempirical and ah initio methods. Some of the most recent of these methods have a few parameters that can be adjusted by the user in order to customize the method for a specific solvent. Such methods are designed to predict ACsoiv and the geometry in solution. They have been included in a number of popular software packages including the AMSOL program, which is a derivative of AMPAC created by Cramer and Truhlar. 

The SM1-SM3 methods model solvation in water with various degrees of sophistication. The SM4 method models solvation in alkane solvents. The SM5 method is generalized to model any solvent. The SM5.42R method is designed to work with HF, DFT or hybrid HF/DFT calculations, as well as with AMI or PM3. SM5.42R is implemented using a SCRF algorithm as described below. A description of the differences between these methods can be found in the manual accompanying the AMSOL program and in the reviews listed at the end of this chapter. Available Hamiltonians and solvents are summarized in Table 24.1. 

POLYRATE (we tested Version 8.0) is a program for computing chemical reaction rates. The MORATE, GAUSSRATE, and AM SOLR ATE programs are derived from POLYRATE and designed to work with the MOPAC, GAUSSIAN, and AMSOL programs, respectively. 

Three popular semiempirical programs, AMP AC, AMSOL, and MOPAC, are actually derivations of the same original code. AMP AC 1.0 and MOPAC 3.0 were both created from Version 2.0 of MOPAC. AMSOL was derived from... 

In addition to ab initio methods, developments for semiempirical methods are being investigated on parallel machines. Notable in this regard are MOPAC > 20 (at the San Diego Supercomputer Center i EPSRC Dares-bury Laboratory ) and AMSOL.122 expected, many of the problems encountered with ab initio codes are also found with these programs. 

Figure 12 Number of publications per year in the CJACS file mentioning semiem-pirical MO programs MOPAC, AMPAC, AMSOL, or ZINDO. The search queries for each curve were (1) mopac, (2) ampac, (3) amsol, and (4) zindo.

Solvent effects were evaluated by different self consistent reaction field (SCRF) procedures i) the parametrisation AM1-SM4 for cyclohexane and AM1-SM2.1 for water, implemented on the AMSOL-V suite of programs,ii) the ab initio Pisa model (interlocking spheres) implemented in the Gamess (Rev,97) package and, with different options, in the Gaussian 94 package. 

The SMx models are available in the program AMSOL (comp.chem.umn.edu/ amsol/). TTie programs SPARTAN, PC SPARTAN, and MaeSPARTAN have the SM2 model for aqueous solutions. SPARTAN and PC SPARTAN Pro have AM1-SM5.4 for aqueous solutions. The SM5.0R model is available in the program OMNISOL (comp.chem.umn.edu/omnisol). 

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