Time Correlation Functions for Gases of Linear Molecules in a Magnetic Field

Time correlation functions for gases of linear molecules in a static homogeneous magnetic field are derived from the set of transport relaxation equations obtained from the linearized WaldmannSnider equation. In particular, the complex autoand cross correlation functions of the friction pressure tensor and the tensor polarization are considered. They are of importance for the viscosity, the depolarized Rayleigh spectrum, and flow birefringence. For the gases HD and C02 their real and imaginary parts are plotted as functions of a reduced time and discussed. Lastly, the influence of a constant magnetic field on the flow birefringence property of a gas of linear molecules in a Couette flow arrangement is treated. The principal axes of the dielectric tensor are rotated about the field direction. For two field orientations the respective angles of rotation are determined. The eigenvalues of the dielectric tensor reveal the tendency of the optical and transport properties of the gas to decouple for increasing field strengths.