Addition of hot hydrogen atoms to 1‐butene in the gas phase and dissociation of excited butyl radicals

Abstract

The reaction of hot hydrogen atoms originating from 253.7-and 228.8-nm photolyses of hydrogen sulfide with 1-butene was investigated. Of the hydrogen atoms undergoing addition a substantial part undergoes it in a first collision (37 and 48% a t 253.7 and 228.8 nm, respectively) yielding highly excited butyl radicals. The ratio of nonterminal to terminal addition is 0.5 and practically does not depend on the energy of the hydrogen atoms over the range of 15-33 kcal/mol. Comparing the results of 229-and 254-nm photolyses of hydrogen sulfide with those of 313-and 334-nm photolyses of hydrogen iodide with the use of the decomposition rate constants of n-butyl radicals calculated by the RRKM methods, the conclusion is reached that the hydrogen atom from H2S photodissociation has 90-95% of the available energy.