Reactions of energetic hydrogen atoms with simple hydrocarbons. Part 2.—Substitution reactions in ethane

Abstract

The products of reaction of recoil tritium atoms with ethane are studied in the presence of Kr and Xe moderators. It is found that the relative yields of substitution products remain essentially unaltered over a wide range of moderation by these moderators or Ne, N₂, CF₄ and He. The relative moderating efficiencies of Ne, Kr, Xe, N₂ and CF₄ are found to be 0.066, 0.042, 0.036, 0.208 and 0.536 respectively. It is proposed that all products, other than HT, may be regarded as resulting from collision of the hot T atom with a carbon atom followed by dissociation of one of the C-ligand bonds. It is suggested that the rapidity of dissociation of a C—H bond may leave the labelled product in a vibrationally excited state which may decay by further C—C or C—H bond rupture.