Comparing reactions of H and Cl with C-H stretch-excited CHD_3

摘要

We report the methyl radical product state distributions for the reactions of H and Cl with CHD_3(v_1 = l,2) at collision energies of 1.53 and 0.18 eV,respectively.Both reactions demonstrate mode selectivity.The resulting state distributions from the H + CHD_3(v_1 = l,2) reactions are well described by a spectator model.The reactions Cl+CHD_3(v_1 = l ,2) exhibit similar behavior,but in some aspects the spectator model breaks down.We attribute this breakdown to enhanced intramolecular vibrational redistribution in the Cl+CHD_3(v_1 = l,2) reactions compared to the H+CHD_3(v_1 = 1,2) reactions,caused by the interaction of the slower Cl atom with the vibrationally excited CHD_3,which is promoted either by its longer collision duration,its stronger coupling,or both.