The thermal conductivity of solid SF 6 , CHCI 3 , C 6 H 6 , and CCl 4 was investigated by the linear-flow method under saturated vapor pressures in the temperature range from 80 K to the corresponding melting temperatures and then recalculated for a constant density of the samples. The contributions of the phonon-phonon and phonon-rotation interactions to the total thermal resistance were separated using the modified method of reduced coordinates. It is shown that the phonon-rotation contribution to the thermal resistance of the crystals decreases as the rotational motion of the molecules attains more freedom.

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The isochoric thermal conductivity of γ-O 2 has been studied on samples of varying density in the temperature interval from 44 K to the onset of melting. The thermal conductivity of nearly free sample decreases at rising temperature along the isochores. It is shown that the absolute value of thermal conductivity in the γ-phase of O 2 is close to its lower limit and most of the heat is transported by «diffusive» modes. The growth of thermal conductivity in γ-O 2 is attributed to the decay of the phonon scattering at the rotational excitations of the molecules and at the short-range magnetic order fluctuations at rising temperature.