Vibrational Excitation and Relaxation of HCl (V=2) State

Abstract

Vibrational fluorescence from V=2 to V=1 state is observed following excitation by a pulsed HCl chemical laser. The time dependence of the fluorescence is used to determine the rate of near‐resonant vibration‐to‐vibration energy transfer, $$\mathrm{HCl}\text{(V=1)+}\mathrm{HCl}\text{(V=1)⇄}\mathrm{HCl}\text{(V=2)+}\mathrm{HCl}\text{(V=0)+Δ E=104\hspace{0.17em}}{\mathrm{cm}}^{\text{−1}}$$ . The cross section for this reaction in the exothermic direction at room temperature has been found to be ${\text{0.73± 0.15× 10}}^{\text{−16}}\hspace{0.17em}{\mathrm{cm}}^{\text{−2}}$ .