Effective collision cross sections governing the effect of an external magnetic field on the thermal conductivity of a pure gas of linear molecules

Using Liouville-space algebra, general expressions are derived for the independent effective collision cross sections governing the thermal conductivity Senftleben–Beenakker effect in a pure gas of linear molecules. These cross sections are presented in terms of S-matrix elements in the total-J representation since it is particularly useful for the dynamical approximation procedures in current use.