Theoretical characterization of the high-pressure phases of PbF2

Citation
A. Costales et al., Theoretical characterization of the high-pressure phases of PbF2, PHYS REV B, 61(17), 2000, pp. 11359-11362
Citations number
22
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
10980121 → ACNP
Volume
61
Issue
17
Year of publication
2000
Pages
11359 - 11362
Database
ISI
SICI code
1098-0121(20000501)61:17<11359:TCOTHP>2.0.ZU;2-M
Abstract
Ab initio perturbed ion calculations were performed for the cubic, orthorho mbic, hexagonal, and monoclinic phases of PbF2. A complete characterization of these phases was achieved in terms of the potential energy surfaces, th e equations of state, and the phase-transition pressures. Thermal effects w ere included via a quasiharmonic nonempirical Debye model. The internal par ameters of the unit cell of each phase were reoptimized at each volume to g enerate the energy surface. The calculated results are in good agreement wi th the experimental data available for the cubic and orthorhombic phases. T he results predict the hexagonal phase to be the high-pressure post-cotunni te structure for PbF2, since the monoclinic phase is seen to collapse into the hexagonal phase during the optimization at high pressures.