Photolysis of Nitrosyl Chloride by Ultra-violet Radiation

Abstract

THE photolysis of nitrosyl chloride was investigated first by Kiss1, and later by Bowen and Sharp2, who found that the quantum yield was 0.5 in both the spectral regions 4380–5000 A, and 4480–5200 A. Kistiakowsky3 investigated the reaction more fully, using essentially monochromatic light derived either from a mercury arc, or from a tungsten filament lamp, both used in conjunction with filters. He concluded that the mean quantum yield for the decomposition over a range of wave-lengths from 6350 A to 3650 A was 2.1. At 3650 A the quantum yield was 2.7, although Kistiakowsky believed that this value was incorrect because of the partial absorption of the ultra-violet radiation by the ‘Pyrex’ windows of the reaction cell. He suggests that the results of Bowen and Sharp disagree with his own either because they used non-monochromatic light, or because they neglected the dark reaction.