title: First stretching overtone of BiH3: an extreme local-mode case for XH3-type molecule?
abstract: The first stretching overtone region of short-lived, formerly inaccessible BiH3 near 3405 cm(-1) has been measured by Fourier-transform infrared spectroscopy with a resolution of 0.0066 cm(-1). Only the 2nu1(A1)/nu1+nu3(E) band system has been observed. Rotational analysis, with transitions reaching J'max=14, has revealed almost perfect local-mode behavior for the upper states denoted as (200A1/E) in the local-mode notation. Ratios of vibration-rotation interaction parameters q(eff)/alpha(eff)(BB) and r(eff)/alpha(eff)(BC), and the appropriate rotational constant differences, are in good agreement with theoretical local-mode limit values. A simple stretching vibrational model reproduces the observed vibrational term values well, and the potential parameters obtained are close to true values.
authors.affiliation: Anorganische Chemie, FB 10, Bergische Universitat, D-42097 Wuppertal, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Jerzembeck
authors.forename: H
authors.initials: H
authors.lastname: Bürger
authors.forename: V
authors.initials: V
authors.lastname: Hänninen
authors.forename: L
authors.initials: L
authors.lastname: Halonen