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Internal rotation study of some sixfold barrier molecules

✍ Scribed by P. C. Chen

Publisher: John Wiley and Sons
Year: 1997
Tongue: English
Weight: 135 KB
Volume: 62
Category: Article
ISSN: 0020-7608
DOI: 10.1002/(sici)1097-461x(1997)62:2<213::aid-qua9>3.0.co;2-z

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✦ Synopsis

Molecular orbital calculations of sixfold barriers in nitromethane, methyl boron difluoride, and trifluoronitromethane were performed by various Hartree᎐Fock and electron correlation methods. In those calculations, staggered and eclipsed conformations are of primary concern. These results indicated that for CH NO and CH BF the staggered 3 2 3 2 conformations are more stable, while CF NO has a more stable conformation in an 3 2 eclipsed form. Both conformations do not differ significantly, which may account for the low internal rotational barrier of each molecule. Values of the barrier calculated by the Møller᎐Plesset perturbation and the quadratic configuration interaction methods did not match the experimental results. However, better internal rotational barrier values of each molecule were observed when the improved better basis sets and the Hartree᎐Fock method were selected.

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