Quantum-Mechanical Kinetic Theory of Loaded Spheres

The transport coefficients of a gas of loaded spheres, that is, spheres in which the centers of mass do not coincide with the geometrical centers, are considered. The amount by which the center of mass is displaced from the center of the sphere is denoted by δ and the diameter of the sphere is σ. The scattering amplitude and cross section are found as power series in δ/σ; the coefficients of the zero, first, and second power of δ/σ are obtained. Using these results, the quantum-mechanical expressions for the relaxation time, and coefficients of shear viscosity, thermal conductivity, and diffusion may be obtained explicitly to second order in δ/σ.