氮化钒热力学性质的第一性原理计算
First principles study of thermodynamic properties of vanadium nitride

通过投影扩大波方法预测了氮化钒的热力学性质, 计算的晶格常数和前人理论实验结果相吻合. 通过准谐德拜模型获得了高温高压下相对体积、体弹模量、热力学常数和热熔的变化情况. 结果表明, 低温低压下, 热力学常数随温度迅速增加, 在较高的温度和压力下, 增长趋于平缓；低温时, 热熔与温度的三次方成正比, 并且高温时接近于杜隆普蒂常数.
Using the projector augmented wave method, we have investigated the thermodynamic properties of vanadium nitride. It is found that our calculated lattice parameters are in excellent agreement with the limited experimental data and the previous theoretical results. Combined with the quasi harmonic Debye model, we also predicted the thermodynamic properties of vanadium nitride (VN). The normalized volume ？？V/V？？？？？？0？？, bulk modulus ？？B？？, thermal expansion ？？α？？ of VN under high temperature and high pressure are also successfully obtained. At low pressure and low temperature, thermal expansion coefficient increases rapidly with increasing temperature. At high temperature and high pressure, the increasing trend is gentle. At low temperatures, ？？C？？v？？ is proportional to ？？T？？？？？？3？？, and ？？C？？？？v inclines to the Dulong Petit limit at higher temperature