First-Principles Molecular Dynamics Calculations of the Equation of State for Tantalum

International Journal of Molecular Sciences

关键词: equation of state;    tantalum;    high pressure;    ab initio calculations;   

DOI  :  10.3390/ijms10104342

来源: mdpi

【 摘 要 】

The equation of state of tantalum (Ta) has been investigated to 100 GPa and 3,000 K using the first-principles molecular dynamics method. A large volume dependence of the thermal pressure of Ta was revealed from the analysis of our data. A significant temperature dependence of the calculated effective Grüneisen parameters was confirmed at high pressures. This indicates that the conventional approach to analyze thermal properties using the Mie-Grüneisen approximation is likely to have a significant uncertainty in determining the equation of state for Ta, and that an intrinsic anharmonicity should be considered to analyze the equation of state.

【 授权许可】

CC BY   
© 2009 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.