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对NaAlSi2O6、MgSiO3、Ca3Al2Si3O12、Ca1.5Mg1.5Al2Si3O12等玻璃进行了低温绝热热容（Cp）测量。测量结果及过去的数据表明，在体系Cao－MgO－Al2O3－SiO2的整个所研究的成玻璃部分中，在高于50K时热容都是组成（误差在±1％以内）的加和函数。考虑到氧配位多面体对低温熵有决定性作用，可以认为，这表明在所有这些玻璃中Si、Al是四面体配位，与结构数据一致，而Ca、Mg依然是八面体配位。相反，碱性铝硅酸盐的热容和熵都不是组成的加和函数，表明加入Al时，碱金属元素的配合数从约6增至9。玻璃振动熵具加和性的热化学效应是：钙、镁铝硅酸盐熔体的混合熵基本上是构型的。对于含碱金属液体来说，振动熵可能对混合熵有明显贡献。在很低的温度下，可能由于中程有序的特定差异，热容与组成的加和性不大好。
The low temperature adiabatic heat capacity (Cp) of glass such as NaAlSi2O6, MgSiO3, Ca3Al2Si3O12, Ca1.5Mg1.5Al2Si3O12 were measured. The results of the measurements and the past data show that the heat capacity above 50 K for all of the investigated glass components of the system Cao-MgO-Al2O3-SiO2 is an additive function of composition (within ± 1% of error). Considering that oxygen-coordinated polyhedrons have a decisive effect on the low-temperature entropy, it can be assumed that this indicates that Si and Al are tetrahedral coordination in all these glasses, consistent with the structural data, while Ca and Mg are still octahedral coordination. In contrast, neither the heat capacity nor the entropy of the basic aluminosilicate is an additive function of the composition, indicating that the number of alkali metal elements is increased from about 6 to 9 when Al is added. The thermo-chemical effect of glass vibration entropies is that the mixed entropy of calcium and magnesium aluminosilicate melts is essentially conformational. For alkali-metal-containing fluids, the vibration entropy may have a significant contribution to the entropy of mixing. At very low temperatures, the sum of heat capacity and composition may not be good due to the specific differences in mid-range order.