Vibrational and rotational energy distribution of ClO produced in reactions of O(1D) atoms with HCl, CCl4, and chlorofluoromethanes

Nascent state-resolved ClO(X 2Π) radicals produced in reactions of O(1D) with HCl, CCl4, CFCl3, CF2Cl2, and CF3Cl have been measured, using vacuum-ultraviolet laser-induced fluorescence of the ClO(C 2Σ−–X 2Π) transition. Rotational temperatures of ClO (X 2Π3/2, v=0 and 1) are 900–1000 K for chlorofluoromethanes and 2050±60 K (v=0) and 1770±180 K (v=1) for HCl. The rotational distribution for the O(1D)+HCl system is interpreted by the orbital-to-rotational angular momentum transfer mechanism. Vibrational level populations of the ClO(v=0–3) products are inverted for CCl4 and chlorofluoromethanes, but not for HCl. Vibrational excitations in the v=0–3 levels are higher for the reactions with the larger available energies.