Open AccessFirst-principle calculations of elastic, electronic and thermodynamic properties of TiC under high pressure
Author(s) -
Bin Wang,
Ying Liu,
Jinwen Ye
Publication year - 2012
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.61.186501
Subject(s) - debye model , pseudopotential , thermal expansion , thermodynamics , materials science , bulk modulus , heat capacity , debye function , elastic modulus , grüneisen parameter , condensed matter physics , debye length , physics , ion , quantum mechanics
First-principle investigations of the elastic, electronic and thermodynamic properties of TiC in NaCl structure under high pressure are conducted by using the plane-wave pseudopotential method and quasi-harmonic Debye model. The obtained lattice parameters, elastic constants and moduli at p=0 GPa and T=0 K are in very good agreement with the available experimental data and other theoretical results. According to the analysis of the density of states, the Ti-C bond becomes stronger with pressure increasing. The values of bulk modulus, thermal expansion coefficient, Debye temperature, entropy, Grüneisen parameter and heat capacity (CV) at different pressures and temperatures are obtained successfully by using the quasi-harmonic Debye model. The influence of pressure on bulk modulus, thermal expansion parameter and Debye temperature is greater than that of temperature. The CV decreases with the increase of pressure under the same temperature and tends to the Dulong-Petit limit at high temperature.