Vibrational product states from reactions of CN− with the hydrogen halides and hydrogen atoms

Infrared chemiluminescence is observed from the C–H stretch manifold ν3 of HCN formed in the gas phase ion–molecule reactions: CN−+HX→HCN(v3)+X−, with (X = Cl, Br, I), and for CN−+H→HCN(v3)+e−. Qualitative information is also obtained for excitation in the bending mode. In each case some excitation is observed in the highest level allowed by energy conservation. Comparison with similar studies of the reactions Cl−+HX shows that the stretching mode of the newly formed bond is less efficiently populated in the HCN case. Emission is observed from CNH (hydroisocyanic acid) formed in the reaction CN−+HI→CNH(v)+I−.