We compare the direct free energy interpolation(DFEI) method and the quasi-harmonic approximation(QHA) in calculating of the equation of states and thermodynamic properties of prototype Al. The Gibbs free energy of Al...We compare the direct free energy interpolation(DFEI) method and the quasi-harmonic approximation(QHA) in calculating of the equation of states and thermodynamic properties of prototype Al. The Gibbs free energy of Al is calculated using the DFEI method based on the high-temperature phonon density of states reduced from classical molecular dynamics simulations. Then, we reproduce the thermal expansion coefficients, the specific heat, the isothermal bulk modulus of Al accurately. By comparing the results from the DFEI method and the QHA, we find that the DFEI method is indeed more accurate in calculating anharmonic properties than the QHA.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.41574076the Young Core Teacher Scheme of Henan Province under Grant No.2014GGJS-108the Fundamental and Cutting-edge Technology Research Program of Henan Province under Grant No.152300410218
文摘We compare the direct free energy interpolation(DFEI) method and the quasi-harmonic approximation(QHA) in calculating of the equation of states and thermodynamic properties of prototype Al. The Gibbs free energy of Al is calculated using the DFEI method based on the high-temperature phonon density of states reduced from classical molecular dynamics simulations. Then, we reproduce the thermal expansion coefficients, the specific heat, the isothermal bulk modulus of Al accurately. By comparing the results from the DFEI method and the QHA, we find that the DFEI method is indeed more accurate in calculating anharmonic properties than the QHA.
