Heat Transfer in Solid Solutions Hydrogen-Deuterium

The thermal conductivity of parahydrogen-orthodeuterium solid solutions with the orthodeuterium concentration of 0.01 to 100% has been investigated in the temperature range from 1.8 K to the melting point. The experimental data have been analyzed in terms of the Callaway model. It has been found that the intensity of phonon scattering by isolated orthodeuterium impurities in solid hydrogen is much higher than that in classical crystals. The impurity additional scattering of phonons has been supposed to be due to variations in force constants and lattice distortions in the vicinity of impurity molecules in quantum crystals. The above effects have been quantitatively estimated. The concentration dependences of the thermal conductivity and phonon scattering intensity have been considered.