A Study on Collision Energy-transfer ofHe（2³S）with SOCl₂ in the Flowing Afterglow System

Dissociative excitation of SOCl₂ by collision with He（2³S） has been studied by observing SO(A³Π-X³Σ) emission in the flowing afterglow system. The effect of SF₆ addition into the He afterglow indicated the excited species SO（A） in the flowing afterglow was produced from primary dissociative excitation process directly by the metstable He（2³S）. The formation rate constant of SO（A） has been determined to be 4.43×10^-11cm^-3∙molecule^-1∙s^-1 by using the reference reaction method. A compraison between the observed formation rate constant and known total quenching rate constant indicated that dissociative excition process is primary exit channel. The nescent vibrational distribution of SO（A） was estimated by extrapotating the steady-state distributions to low prossure. Vibrational relaxation of SO（A,v’） in He-Ar-SOCl₂ mixtures was estimated.