Low‐temperature specific heat of Li2O·Al2O3·nSiO2 glasses and keatite‐phase glass ceramics

摘要

The specific heat of Li2O·Al2O3·nSiO2 glasses and keatite‐phase glass ceramics, with n=4,6,8,10,12 has been measured between 1.5 and 6 K. The temperature dependence of the specific heat was determined by using several least‐squares fits to the data and found to be of the form C=C1T+C3T3. Generally, for a given composition, the magnitude of C3 for the glass ceramic is larger than the value for the corresponding glass. For a given structure, C3 also shows a composition dependence. Estimates for C1 show a dependence on both composition and structure. The results are compared to those obtained for vitreous silica.