Abstract The structural, mechanical, electronic and thermodynamic properties of cubic TiC compounds under different pressures have been investigated by using the first principles method. The cubic TiC compounds still maintains bcc lattice under the pressure up to 170 GPa, and the lattice constants decrease with the increasing pressure. The strength of cubic TiC compounds can be improved by the increasing pressure based on the analysis of mechanical properties. The values of B/G increase with the increase of pressure, indicating that pressure can improve the ductility of cubic TiC compounds. However, the B/G values are all less than 1.75, which indicates that cubic TiC compounds is brittle phase. The amount of charge transferred from Ti→C atoms decreases with the increasing pressure. Thermodynamic properties such as Debye temperature, free energy, entropy, enthalpy and heat capacity are also discussed.

中文翻译：

---

不同压力下立方 TiC 化合物的结构、机械、电子和热力学性质：第一性原理研究

摘要 采用第一性原理方法研究了立方体TiC化合物在不同压力下的结构、机械、电子和热力学性质。立方体TiC化合物在高达170 GPa的压力下仍保持bcc晶格，并且晶格常数随着压力的增加而减小。根据力学性能分析，增加压力可以提高立方TiC化合物的强度。B/G 值随着压力的增加而增加，表明压力可以提高立方 TiC 化合物的延展性。但 B/G 值均小于 1.75，说明立方 TiC 化合物为脆性相。从 Ti→C 原子转移的电荷量随着压力的增加而减少。热力学性质，如德拜温度、自由能、