Nature of the change in the rotational barrier of the methyl group due to S0→S1 excitation

Hiromi Nakai, M. Kawai

    Research output: Contribution to journalArticle

    36 Citations (Scopus)

    Abstract

    Internal rotation of the methyl group in o- and m-fluorotoluenes has been investigated by the ab initio molecular orbital method. The calculated rotational barriers in the S0 and S1 states are in reasonable agreement with experimental values. Steric and electrostatic effects are not important for the changes in the rotational barriers. An electronic effect is found to be the most significant. Especially, the rotational barriers in the S1 states are determined by the stability of the LUMOs, which involves a new type of hyperconjugation between the ortho-carbon and the hydrogens of the methyl group.

    Original languageEnglish
    Pages (from-to)272-276
    Number of pages5
    JournalChemical Physics Letters
    Volume307
    Issue number3-4
    Publication statusPublished - 1999 Jul 2

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    Molecular orbitals
    Hydrogen
    Electrostatics
    Carbon
    excitation
    molecular orbitals
    electrostatics
    carbon
    hydrogen
    electronics

    ASJC Scopus subject areas

    • Physical and Theoretical Chemistry
    • Spectroscopy
    • Atomic and Molecular Physics, and Optics

    Cite this

    Nature of the change in the rotational barrier of the methyl group due to S0→S1 excitation. / Nakai, Hiromi; Kawai, M.

    In: Chemical Physics Letters, Vol. 307, No. 3-4, 02.07.1999, p. 272-276.

    Research output: Contribution to journalArticle

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