Translational energy dependence of reaction dynamics in kinematically constrained systems. Xe(3P2)+ HCl, HBr, Hl and CH3l

Abstract

The fully dispersed chemiluminescence spectra excited by reactions of Xe(³P₂) with Hl, HBr, HCl and CH₃l have been recorded under superthermal beam–Maxwellian gas conditions. Direct spectral inversion has enabled determination of the rare-gas halide product vibrational energy distributions at selected collision energies in the range 〈E_T〉≈(4–90)kJ mol^–1. The mean vibrational energy disposals 〈E^′_v〉 are found to increase linearly with the mean collision energy 〈E_T〉. This result, together with earlier measurements of reactive excitation functions (K. M. Johnson, J. P. Simons, P. A. Smith, C. Washington and A. Kvaran, Mol. Phys., 1986, 57, 255) and with the kinematic constraint on the dynamics, allows separate estimates of the mean energy disposals into rotation and translation, as well as the mean reactive cross-section.