THERMAL-CONDUCTIVITY AND HEAT-CAPACITY OF AMORPHOUS SIO2 - PRESSURE AND VOLUME DEPENDENCE

The thermal conductivity (lambda) and heat capacity per unit volume (rho-c(p)) of amorphous SiO2 have been measured under hydrostatic pressure up to 1 GPa at room temperature using a transient two-strip method. The thermal conductivity was found to decrease slightly with increasing pressure. For the volume dependence of lambda expressed by the Bridgman parameter, g = -(partial derivative ln lambda/partial derivative ln V)T, we obtained g = -1.5. The experimental value of g is discussed in conjunction with predicted g-values based on theoretical models of lambda(T). The specific heat capacity (c(p)) calculated from measured rho-c(p) was found to be almost constant with increasing pressure.