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RESEARCH PRODUCT
High-pressure study of the behavior of mineral barite by x-ray diffraction
Armando BeltránDavid Santamaría-pérezDaniel ErrandoneaD. Martinez-garciaRaquel Chuliá-jordánAlfredo SeguraLourdes GraciaCh. Ferrer-rocaOscar GomisGaston Garbarinosubject
DiffractionPhase transitionMaterials scienceHigh-pressureAnalytical chemistryDensityHigh pressure (Technology)BaSO4symbols.namesakeBariteCationsPhase (matter)Barium compoundsCompostos de bariRamanMineralTemperatureOxidesTecnologia de les altes pressionsCondensed Matter PhysicsX-ray diffractionElectronic Optical and Magnetic MaterialsFISICA APLICADAHigh pressureTransitionX-ray crystallographysymbolsOrthorhombic crystal systemRaman spectroscopyBASO4description
In this paper, we report the angle-dispersive x-ray diffraction data of barite, BaSO 4, measured in a diamond-anvil cell up to a pressure of 48 GPa, using three different fluid pressure-transmitting media (methanol-ethanol mixture, silicone oil, and He). Our results show that BaSO 4 exhibits a phase transition at pressures that range from 15 to 27 GPa, depending on the pressure media used. This indicates that nonhydrostatic stresses have a crucial role in the high-pressure behavior of this compound. The new high-pressure (HP) phase has been solved and refined from powder data, having an orthorhombic P2 12 12 1 structure. The pressure dependence of the structural parameters of both room- and HP phases of BaSO 4 is also discussed in light of our theoretical first-principles total-energy calculations. Finally, a comparison between the different equations of state obtained in our experiments is reported. © 2011 American Physical Society.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2011-08-02 | Physical Review B |