Processes of photodissociation of free alkyl iodide molecules by 254 nm radiation

The quantum yields of the primary products of the photodissociation of CH₃I, C₂H₅I, C₄H₉I, CH₃CHIC₂H₅, and (CH₃)₂CHCH₂I were determined in the spectral range 254 nm. It was found that the main primary photolysis process was the splitting off of atomic iodine in the ²P_l/2 excited state and the quantum yield was 0.9, 0.79, 0.67, 0.80, and 0.75, respectively. The quantum yields of the formation of atomic iodine in the ²P_3/2 state were 0.1, 0.20, 0.32, 0.09, and 0.24, respectively. Regrouping photodissociation processes producing stable HI and C_nH_2n molecules (Φ=0.01–0.1) were observed. The quantum yields of other primary photodissociation products were of the order of 2×10^–2–10^–4.