title: Spectroscopic study on deuterated benzenes. I. Microwave spectra and molecular structure in the ground state.
abstract: We observed microwave absorption spectra of some deuterated benzenes and accurately determined the rotational constants of all H/D isotopomers in the ground vibrational state. Using synthetic analysis assuming that all bond angles are 120°, the mean bond lengths were obtained to be r0(C-C) = 1.3971 Å and r0(C-H) = r0(C-D) = 1.0805 Å. It has been concluded that the effect of deuterium substitution on the molecular structure is negligibly small and that the mean bond lengths of C-H and C-D are identical unlike small aliphatic hydrocarbons, in which r0(C-D) is about 5 mÅ shorter than r0(C-H). It is considered that anharmonicity is very small in the C-H stretching vibration of aromatic hydrocarbons.
authors.affiliation: Division of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Sachi
authors.initials: S
authors.lastname: Kunishige
authors.affiliation: Division of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Katori
authors.affiliation: Division of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Baba
authors.affiliation: Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Nakajima
authors.affiliation: Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan.
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Endo