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First-principles thermoelasticity of bcc iron under pressure

Xianwei Sha·R. E. Cohen
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Abstract

We investigate the elastic and isotropic aggregate properties of ferromagnetic bcc iron as a function of temperature and pressure by computing the Helmholtz free energies for the volume-conserving strained structures using the first-principles linear response linear-muffin-tin-orbital method and the generalized-gradient approximation. We include the electronic excitation contributions to the free energy from the band structures, and phonon contributions from quasi-harmonic lattice dynamics. We make detailed comparisons between our calculated elastic moduli and their temperature and pressure dependences with available experimental and theoretical data.

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Xianwei Sha, R. E. Cohen. 2006-12-12. First-principles thermoelasticity of bcc iron under pressure. https://doi.org/10.1103/physrevb.74.214111

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