Lin, Y;
Cohen, RE;
Stackhouse, S;
Driver, KP;
Militzer, B;
Shulenburger, L;
Kim, J;
(2014)
Equations of state and stability of MgSiO3 perovskite and post-perovskite phases from quantum Monte Carlo simulations.
PHYSICAL REVIEW B
, 90
(18)
, Article ARTN 184103. 10.1103/PhysRevB.90.184103.
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Abstract
We have performed quantum Monte Carlo (QMC) simulations and density functional theory calculations to study the equations of state of MgSiO3 perovskite (Pv, bridgmanite) and post-perovskite (PPv) up to the pressure and temperature conditions of the base of Earth's lower mantle. The ground-state energies were derived using QMC simulations and the temperature-dependent Helmholtz free energies were calculated within the quasiharmonic approximation and density functional perturbation theory. The equations of state for both phases of MgSiO3 agree well with experiments, and better than those from generalized gradient approximation calculations. The Pv-PPv phase boundary calculated from our QMC equations of state is also consistent with experiments, and better than previous local density approximation calculations. We discuss the implications for double crossing of the Pv-PPv boundary in the Earth.
Type: | Article |
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Title: | Equations of state and stability of MgSiO3 perovskite and post-perovskite phases from quantum Monte Carlo simulations |
Open access status: | An open access version is available from UCL Discovery |
DOI: | 10.1103/PhysRevB.90.184103 |
Publisher version: | http://dx.doi.org/10.1103/PhysRevB.90.184103 |
Language: | English |
Additional information: | ©2014 American Physical Society |
UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences |
URI: | https://discovery.ucl.ac.uk/id/eprint/1461760 |
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