Transport Properties of a Gas of Diatomic Molecules. V. GPS Calculation of the Rotational Relaxation Time of theArsngbnd;N2System

摘要

The moments of the probability density function for rotationally inelastic scattering of theArsngbnd;N2system were computed, in Paper XVI of a series on molecular collisions, by both generalized phase shift (GPS) and classical trajectory (CT) methods. In the present paper, it is shown that inclusion of the term of zero order inhslash;in a semiclassical expansion of the generalized phase shift modifies the classical limit expressions for the moments. TheArsngbnd;N2system is reconsidered and the first and second moments calculated to the lowest nonzero order in the anisotropy of the interaction potential. The results of this calculation indicate a marked improvement of the first moment over the previous GPS results as compared with the CT results. The development is extended by integrating the moments over the impact parameter and the translational and rotational energies to obtain rotational collision numbers for theArsngbnd;N2system. These collision numbers are compared with those obtained by classical trajectory methods.