Effects of Correlated Rotation of Linear Molecules in the Low‐Temperature Dynamics and Thermodynamics of Weak Molecular Solutions

Abstract

The paper proposes a pseudospin approach to describe low-temperature dynamics and thermodynamics of weak molecular solutions of linear molecules in atomic cryomatrices. On the basis of a microscopic Hamiltonian, a direct analogue of a weak ortho-parahydrogen solution, the characteristics energies of various types of intermolecular interactions are estimated, i.e. the direct quadrupole-quadrupole one and the indirect ones, dynamic and static, which involve phonons. The thermodynamic characteristics (specific heat, thermal expansion, and the Griineisen parameter) of the rotational subsystem of the 14N2-Ar solution are calculated with consideration of longrange correlations in the molecule rotation. A comparison with experimental data on the specific heat of 14N,-Ar is made.