Kinetics of the vibrational deactivation of OH X 2II (v = 3, 2, 1) with hydrides and reduced sulfides

Abstract

The deactivation kinetics of vibrationally excited OH X ² II were studied using the pulsed laser photolysis–pulsed laser induced fluorescence technique. Photolysis of O ₃ at 266 nm was used to produce O( ¹ D) which reacted rapidly with a precursor to produce OH(v). Temporal profiles of OH(v) were obtained by exciting off-diagonal (Δv = −1) transitions in the A–X band of OH and monitoring the diagonal, blue-shifted fluorescence. Deactivation rate coefficients for OH (v = 3, 2, 1) with H ₂ O and CH ₄ and for OH (v = 2, 1) with NH ₃ , CS ₂ , (CH ₃ ) ₂ S, CH ₃ SH and CH ₃ Br were obtained. The mechanisms of deactivation and the relationship of the deactivation rate coefficients to the thermal association rate coefficients for OH complexes are discussed.