2001/11/12 by Oğuz Gülseren, O. Gulseren, R. E. Cohen +1 · 1 citation
Earth and Planetary Sciences · Materials Science · Physics and Astronomy · #Boron and Carbon Nanomaterials Research #High-pressure geophysics and materials #Superconductivity in MgB2 and Alloys #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.65.064103
published as Phys. Rev. B 65, 064103 (2002) · To be appear in Physical Review B
arxiv created 2001/11/12 · openalex publication_date 2002/01/03 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We have investigated the thermoelasticity of body-centered-cubic (bcc) tantalum from first principles by using the linearized augmented plane wave and mixed-basis pseudopotential methods for pressures up to 400 GPa and temperatures up to 10 000 K. Electronic excitation contributions to the free energy were included from the band structures, and phonon contributions were included using the particle-in-a-cell (PIC) model. The computed elastic constants agree well with available ultrasonic and diamond-anvil cell data at low pressures, and shock data at high pressures. The shear modulus c44 and the anisotropy change behavior with increasing pressure around 150 GPa because of an electronic topological transition. We find that the main contribution of temperature to the elastic constants is from the thermal expansivity. The PIC model in conjunction with fast self-consistent techniques is shown to be a tractable approach to studying thermoelasticity.