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Ab initio and molecular mechanics (MM2 and MM3) calculations of positively charged conjugated nitrogen-containing compounds

โœ Scribed by McGaughey, Georgia B.; Stewart, Eugene L.; Bowen, J. Phillip

Publisher
John Wiley and Sons
Year
1996
Tongue
English
Weight
726 KB
Volume
17
Category
Article
ISSN
0192-8651

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โœฆ Synopsis

Ab initio calculations have been carried out on s-trans-Nvinylmethyleneammonium, pyridinium, and related compounds to obtain rotational barriers, structures, and vibrational frequencies. The restricted Hartree-Fock (RHF) level of theory with 6-31G** basis set was used for these calculations. In addition, the MM2(91) and MM3(94) force fields have been parameterized to calculate these positively charged nitrogen-containing compounds. A bond order term was incorporated in the force field to reproduce accurately the rotational barriers of s-trans-N-vinylmethyleneammonium and related compounds. Molecular mechanics geometries and vibrational frequencies compare well with those calculated by ab initio methods.

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