Odd terms in angular momentum and transport properties of polyatomic gases in a field

Abstract

When the Waldmann-Snider collision superoperator is self-adjoint, terms in a tensorial expansion for the determination of the thermal conductivity and viscosity of a dilute polyatomic gas which are odd in the angular momentum are decoupled from those which are even and hence vanish. Otherwise such terms exist and can be detected in the angular dependence of the change of transport properties in an external field. The contribution of a few odd terms is calculated for both thermal conductivity and viscosity and shown to be opposite to the main part of the effect and to lead to deviations of the saturation ratios between the effects obtained under different relative orientations of the magnetic field and the gradients.