High-precision calculation of the equation of state and crystallographic phase stability for aluminum

Journal Article · Thu Feb 01 04:00:00 EST 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.53.3007· OSTI ID:278722

Boettger, J C ^[1]; Trickey, S B ^[2]

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1. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
2. Quantum Theory Project, Departments of Physics and of Chemistry, University of Florida, Gainesville, Florida 32611 (United States)

High-precision, all-electron, full-potential, local-density approximation (LDA) calculations are used to determine the static lattice equation of state (EOS) and crystalline phase stability of Al to 1 TPa. The low-pressure properties found here are consistent with the results of other nonrelativistic LDA calculations, but differ significantly from the results of relativistic LDA or gradient-dependent approximation calculations. The theoretical 300-K isotherm for fcc Al, obtained by adding phonon effects to the static lattice EOS, is in reasonable agreement with room temperature data up to 220 GPa. The predicted static-lattice phase sequence for Al is fcc{r_arrow}hcp{r_arrow}bcc with the transitions occurring at 205{plus_minus}20 GPa and 565{plus_minus}60 GPa. Estimation of the possible impact of phonons on the fcc{r_arrow}hcp transition produces a fairly firm upper bound of 290 GPa (282) on the room-temperature (zero temperature) fcc{r_arrow}hcp transition pressure. This result suggests that a recent diamond-anvil-cell experiment came very close to achieving the fcc{r_arrow}hcp transition. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 278722
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 6 Vol. 53; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM
AMBIENT TEMPERATURE
CRYSTAL STRUCTURE
ELECTRONIC STRUCTURE
EQUATIONS OF STATE
PHASE STUDIES
PRESSURE DEPENDENCE
STABILITY
VERY HIGH PRESSURE