Distribution function for the orientational order parameters in solid H2 and D2

A model for the distribution function P(σ,η) for the axial and eccentric orientational order parameters σ and η is proposed for a system of quadrupoles which represents the situation in solid H2 and D2. It is based on a plausible approximation to the exact one-particle orientational density matrix for J=1 molecules in the randomly distributed (J=1)X(J=0)(1-X) solid, where X is the molar concentration of the J=1 component. The properties of …