LIF Studies of the Ã1A' States of BiOH and BiOD

Electronic spectra of the recently discovered BiOH and BiOD radicals have been studied by means of laser-induced fluorescence measurements in the 400-1000 nm range. Laser excitation spectra observed in the range 430-450 nm are attributed to transitions from the &Xtilde;1A' ground state to the theoretically predicted Ã1A' state. Fluorescence spectra from the Ã1A',nu'3 = 0, 1 levels consist of short nu"3 progressions to the lower states &Xtilde;1A', &Xtilde;3A', and ã1A'. Laser excitation spectra in the range 580-620 nm contain bands with both DeltaKa = 0 and DeltaKa = +/-1 subbands. They are attributed to hybrid bands of the Ã1A' <-- &Xtilde;3A' transition. Analyses of the spectra have yielded vibronic energy levels of the &Xtilde;1A', &Xtilde;3A', ã1A', and Ã1A' states of both isotopes and effective rotational constants A - 1/2(B + C) and DK for some levels. The radiative lifetime of the Ã1A',000 state was found to be 0.92 +/- 0.03 µs. Copyright 1998 Academic Press.