THERMOPHYSICAL PROPERTIES AND MECHANISM OF HEAT-TRANSFER OF NONSTOICHIOMETRIC CU2-XS

The specific heat capacity (C-p), thermal conductivity (lambda), and thermal diffusivity (a) are measured for polycrystalline Cu2-xS (0 < x < 0.2) in the temperature range 300 to 600 K. Measurements are performed using the flash method. These properties are found to exhibit anomalous behaviour in the vicinity of phase transformation temperatures for each composition. The results show that the mechanism of heat transfer is due mainly to phonons, whereas the contribution of electrons and dipoles are very small indeed.