High-Temperature Thermal Conductivity of Insulating Crystals: Relationship to the Melting Point

The Lindemann melting rule is used to eliminate the elastic constant from the thermal conductivity formula proposed by Lawson. The thermal conductivity is thus obtained as a function of density, atomic weight, and melting temperature. The introduction of a dependence on bond character allows a major fraction of the available high-temperature thermal conductivity data to be reproduced within a factor of two. A dependence of thermal conductivity on mass ratio of the type found theoretically by Blackman for diatomic crystals is observed.