Kinetic studies of the reaction NH2 + H2S

Amidogen (NH2) radicals were generated by pulsed laser photolysis of ammonia precursor at 193 nm, and monitored by laser-induced fluorescence excited at 570.3 nm. Experiments were conducted in argon bath gas with traces of hydrogen sulfide (H2S) at pressures of 9–25 mbar and temperatures of 294–820 K. The NH2 + H2S rate constant was found to be (4.30 ± 0.25) × 10−13 cm3 molecule−1 s−1 independent of temperature. The rate constant for removal of vibrationally-excited NH2 (0, 1, 0) by H2S was estimated as (1.5 ± 0.2) × 10−11 cm3 molecule−1 s−1, which includes both physical quenching and chemical reaction.