Vibrational relaxation of the bending modes of D<inf>2</inf>O, D <inf>2</inf>S, and H<inf>2</inf>Se gas mixtures

Abstract

The method of laser-excited vibrational fluorescence has been used to measure vibrational relaxation of the bending modes ν2 of H 2Se and D2S in gas mixtures at 295 K. For H2Se relaxed by H2Se, H2, D2, He, and N2 rates of 30±2, 11±1, 3.4±0.2, 1.5±0.1, and 1.1±0.1 (all×10-13 cm3 molecule-1 s-1 were found). For D2S relaxed by D2S and by N2, rates are 5.5±0.6 and (0.12-0.37) (both ± 10 -13 cm2 molecule-1 s-1). Fluorescence from HDO (ν2) following excitation of D2O (ν2) gave a rate for vibration-vibration transfer of a bending quantum from D2O to HDO of about (1.4±0.6)×10 -11 cm3 molecule-1 s-1. D 2O (ν2) is relaxed to translation and rotation at approximately the same rate by HDO as by D2O. © 1982 American Institute of Physics.