Effect of magnetic and electric fields on the transport properties of polyatomic gases. I. Formal theory

The changes in the coefficients of shear viscosity and thermal conductivity caused by a homogeneous external field are considered for a single-component, dilute gas of spin-zero, polyatomic molecules. The quantum mechanical equations for these Senftleben-Beenakker effects are solved by an iterative technique which is especially suited to a series of restricted distorted wave approximations to the transition matrix. In this manner more rigorous and more physical reasons are found for the dominance of certain terms in the expansions usually employed to solve such equations. The final expressions for the Senftleben-Beenakker effects are in terms of ``collision integrals'' which are greatly simplified by using group theoretical methods to completely and explicitly handle the m-type quantum numbers.