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Comparison of NDDO and quasi-ab initio approaches to compute semiempirical molecular electrostatic potentials

✍ Scribed by C. Alhambra; F. J. Luque; Modesto Orozco

Publisher: John Wiley and Sons
Year: 1994
Tongue: English
Weight: 785 KB
Volume: 15
Category: Article
ISSN: 0192-8651
DOI: 10.1002/jcc.540150103

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✦ Synopsis

The suitability of the two most widely used strategies to compute semiempirical MEPs is examined. For this purpose, MEP minima, electrostatic charges, and dipoles for a large number of molecules were computed at the AM1, MNDO, and PM3 levels using both the NDDO strategy developed by Ferenczy, Reynolds, and Richards and our own quasi-ab initio method. Results demonstrate that the quasi-ab initio is preferred over the NDDO method for the computation of MEP minima. It is also found that the best set of semiempirical charges and dipoles are obtained using either the AM1 NDDO or the MNDO quasi-ab initio methods. In these two cases, the quality of the results is fully comparable with 6-31G* values. Sons, Inc.

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