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 Å, and 4480–5200 Å. 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 Å to 3650 Å was 2.1. At 3650 Å 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.