Generation of NH(a1△) in the 193 nm photolysis of ammonia

We report the observation of NH(a 1Δ) formation in a one-photon process during the ArF laser (193 nm) photolysis of ammonia. We have used laser-induced fluorescence to detect NH(a) and ND(a) and report the rotational and vibrational populations generated. We have also reinvestigated the generation of NH(a) in the 248 nm photolysis of HN3 and find substantial vibrational excitation in contrast to the results of previous workers. We give estimates for the quantum yields for NH(a) and ND(a) in the photolysis of ammonia based on comparison with the yield in 248 nm photolysis of HN3.