对爱因斯坦模型的修正及考虑热效应的三个通用状态方程(英文)

Modified Einstein Model to Consider Thermal Effect and Applied to Three Universal Equations of State

对固体考虑热效应的爱因斯坦模型进行了修正。指出考虑热效应的通用状态方程中不应该包含零点振动项,方程参数不应该直接取为参考温度下的实验值VR、BR、B′R和γRG,而应该取为零温下的数值V0、B0、B′0和γ0G;提出了一种从VR、BR、B′R和γRG求解V0、B0、B′0和γ0G的方法。将提出的方法应用于三个典型的通用状态方程,包括Baonza、mMNH和Vinet方程。数值结果表明,利用相同的实验参数对三个方程解出的参数,以及预测的零压和低压下的热物理性质差异很小,而且都与实验数据符合很好。这些结果表明,在零压和低压下预测热物理性质的精确度不足以用来判断各种通用状态方程的适用性。

The Einstein model to consider thermal effect in universal equations of state （UEOS） is modified. It is proposed that the zero-point vibration term should be deleted in a thermal UEOS,and the parameters can not be directly taken as experimental data at a reference temperature,VR ,BR ,BR′ and γR^G, but their values at absolute zero temperature,V0 ,B0 ,B0′ and γ0^G. An approach is proposed to solve V0 ,B0 ,B0′ and γ0^G from VR, BR,BR′ and γR^G. The approaches are applied to three typical universal EOSs,including the Baonza, mMNH and Vinet EOSs. The numerical results show that the solved values of parameters are almost identical for different EOSs. And the thermo-physical properties predicted through different EOSs are almost identical at zero and low-pressure conditions,once the same approach and input experimental data are used to solve parameters. It is concluded that the prediction of thermo-physical properties at zero and low-pressure conditions cannot be taken as the criteria to judge the applicability of a universal EOS.