Alignment dependence of the NH2 chemiluminescence in the reaction of Ar(3P) atoms with the aligned NH3 molecules

An alignment dependence of the NH2(A-X) chemiluminescence was studied in the reaction of the aligned NH3 molecules and the metastable Ar(3P) atoms by using hexapole state selection. The NH2 emission intensities were analyzed by a hard-sphere model for the NH3 molecule. The ratio of the emission cross sections for the head-on attack and the side-on attack was found to be σh/σs = 1.2 ± 0.2. The observed alignment dependence is discussed in terms of the interaction between molecular orbitals of NH3 and the atomic orbital of Ar(3P)