Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (06): 1664-1668.doi: 10.3866/PKU.WHXB20100607

• QUANTUM CHEMISTRY AND COMPUTATION CHEMISTRY • Previous Articles     Next Articles

Phase Transition and Thermodynamic Properties of TiO2

HU Yan-Fei, JIANG Gang, MENG Da-Qiao, KONG Fan-Jie   

  1. Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, P. R. China; National Key Laboratory for Surface Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621907, Sichuan Province, P. R. China
  • Received:2010-01-11 Revised:2010-01-31 Published:2010-05-28
  • Contact: JIANG Gang E-mail:gjiang@scu.edu.cn

Abstract:

The phase transition of TiO2 from the rutile structure to the fluorite structure under pressure was investigated by the first principles plane-wave pseudopotential density functional theory method. The thermodynamic properties of the rutile and fluorite structures for TiO2 were obtained by the quasi-harmonic Debye model. The results obtained are in good agreement with the experimental data and other theoretical results. We found that the rutile-to-fluorite transition of TiO2 occurred at 47.74 GPa from the Gibbs energy calculations. Moreover, the dependence of the relative volume (V/V0 ), the Debye temperature (Θ) and the heat capacity (CV) on the pressure (p)as well as the heat capacity (CV) on the temperature (T) were also successfully obtained.

Key words: Density functional theory, TiO2, Thermodynamic property, Phase transition, Quasi-harmonic Debye model

MSC2000: 

  • O641