Premium
Ab initio and molecular mechanics (MM2 and MM3) calculations of positively charged conjugated nitrogen‐containing compounds
Author(s) -
McGaughey Georgia B.,
Stewart Eugene L.,
Bowen J. Phillip
Publication year - 1996
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/(sici)1096-987x(199609)17:12<1395::aid-jcc2>3.0.co;2-f
Subject(s) - ab initio , chemistry , basis set , computational chemistry , force field (fiction) , ab initio quantum chemistry methods , molecular mechanics , pyridinium , conjugated system , molecular physics , atomic physics , density functional theory , molecule , molecular dynamics , physics , quantum mechanics , organic chemistry , polymer
Ab initio calculations have been carried out on s‐trans‐N ‐vinylmethyleneammonium, 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 parameterizedto calculate these positively charged nitrogen‐containing compounds. A bond order termwas 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. © 1996 by John Wiley & Sons, Inc.