Vibrational Relaxation of Shock-Heated Cl2: Effects of CO, HCl, and DCl

Abstract
The vibrational relaxation of pure Cl2 in the temperature range 400–1400°K, and of binary mixtures of Cl2 with CO, HCl, and DCl in the range 400–1100°K has been studied behind incident shock waves by time‐resolved measurement of the postshock density gradient using a laser‐beam deflection technique. Results obtained for pure Cl2 are more precise than those previously available at these temperatures, and are in excellent agreement with lower‐temperature ultrasonic data. The effect of CO relative to Cl2 is found to be much less than indicated by previous data, and is attributed solely to the lower Cl2–CO reduced collision mass. The effects of HCl and DCl are large, particularly at low temperatures, e.g., HCl is ≈100 times more effective than Cl2 at 400°K. HCl is ≈2–4 times more effective than DCl, depending on the temperature. The relative efficiencies are interpreted as a strong indication of rotational effects.

This publication has 23 references indexed in Scilit: