Measurements of the diffusion coefficients of atomic chlorine in rare gases

Abstract

The technique for measuring the diffusion coefficients of reactive atomic species through their radiative recombination reactions is applied to multicomponent mediums. A series of diffusion coefficients of chlorine atoms in chlorine molecules mixed with rare gases M(He, Ne, Ar, Kr, and Xe) were measured for various Cl2 and M mole fractions. By extrapolating to zero molecular chlorine pressure, the diffusion coefficients of chlorine atoms in rare gases were obtained. The measured values of the diffusion constant are DCl–He =0.75±0.12, DCl–Ne =0.32±0.05, DCl–Ar =0.19±0.03, DCl–Kr =0.14±0.02, and DCl–Xe =0.12±0.02 cm2/s, respectively, at 296 K and 1 atm rare gas pressure. The corresponding hard sphere collision diameter of chlorine atoms in rare gases was calculated and a comparison was made between the diffusion coefficients of Cl–rare gas and Ar–rare gas systems at 296 K.