title: Spectroscopy of Ar-SH and Ar-SD. I. Observation of rotation-vibration transitions of a van der Waals mode by double-resonance spectroscopy.
abstract: Rotation-vibration transitions of a van der Waals bending vibration, P = 1/2 <-- 3/2, of the Ar-SHSD (X 2pi) complexes in the electronic ground state have been observed by applying newly developed microwave-millimeter-wave double-resonance spectroscopy. The rotational energy-level structure for the two isotopomers, with hyperfine structure due to the hydrogen or deuterium nuclei and parity doublings in the P = 1/2 state, has now been clarified. Detailed explanation of the double-resonance technique is also given.
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: Yoshihiro
authors.initials: Y
authors.lastname: Sumiyoshi
authors.forename: Hajime
authors.initials: H
authors.lastname: Katsunuma
authors.forename: Kohsuke
authors.initials: K
authors.lastname: Suma
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Endo