The production and subsequent relaxation of vibrationally excited OH in the reaction of atomic oxygen with HBr

A fast discharge flow apparatus equipped for EPR detection of radicals has been used to investigate the reaction O + HBr → OH + Br. At 295°K, measurements showed that more than 97% of all OH produced in this reaction was formed initially in its first vibrationally excited state. Rate constants for physical deactivation of OH(v = 1) by O(3P), Br(2P3/2), H2O, and HBr were measured as (1.45 ± 0.25) × 10−10, (6.4 ± 2.4) × 10−11, (1.35 ± 0.50) × 10−11, and < 10−12 cm3/molec·sec, respectively.