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Calculations of molecular vibrational frequencies using semiempirical methods

✍ Scribed by Michael B. Coolidge; John E. Marlin; James J. P. Stewart

Publisher: John Wiley and Sons
Year: 1991
Tongue: English
Weight: 446 KB
Volume: 12
Category: Article
ISSN: 0192-8651
DOI: 10.1002/jcc.540120807

No coin nor oath required. For personal study only.

✦ Synopsis

PM3 calculations of molecular vibrational frequencies are reported for 61 molecules. All techniques were applied to both well-behaved and badly behaved systems. Overall, MIND0/3 and MNDO were found to contain rather large errors whereas AM1 and PM3 were relatively accurate. Since no technique does well for all molecules, the technique used should be chosen based on the molecular vibration of interest. in general, AM1 and PM3 together provide fairly accurate resuits.

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