Kinetics of photolysis of nitric acid vapour. Part 1.—Direct photolysis at low conversion

Abstract

The direct photolysis of nitric acid has been studied at 2650 and 2537 Å at small conversions. According to the experimental results, a hydroxyl radical and a NO₂ molecule are formed in the primary process. The primary quantum yields are 0.1 and 0.3 at wave lengths 2650 and 2537 Å, respectively. The experiments with added oxygen indicate that the contributions of the excited singlet and triplet states to the decomposition are comparable at 2650 Å; however, at 2537 Å the decomposition originates almost exclusively from the excited singlet state.