Ab initio quasiharmonic equations of state for dynamically stabilized soft-mode materials

Article

关键词: MOLECULAR-DYNAMICS;    MGSIO3 PEROVSKITE;    LATTICE-DYNAMICS;    PHASE-TRANSITIONS;    FIRST-PRINCIPLES;    MAGNESIUM-OXIDE;    LOWER MANTLE;    PSEUDOPOTENTIALS;    SIMULATIONS;    PHONONS;   

DOI  :  10.1103/PhysRevB.65.184104

来源: SCIE

【 摘 要 】

We introduce a method for treating soft modes within the analytical framework of the quasiharmonic equation of state. The corresponding double-well energy-displacement relation is fitted to a functional form that is harmonic in both the low- and high-energy limits. Using density-functional calculations and statistical physics, we apply the quasiharmonic methodology to solid periclase (MgO). We predict the existence of a B1-B2 phase transition at high pressures and temperatures.

【 授权许可】

Free