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RESEARCH PRODUCT
CaSO4 and its pressure-induced phase transitions. A density functional theory study
Lourdes GraciaArmando BeltranDaniel ErrandoneaJuan Andréssubject
Phase transitionAnhydriteCrystallographyLiquid crystalschemistry.chemical_elementThermodynamicsAnhydriteCalciumInorganic Chemistrychemistry.chemical_compoundCrystallographychemistryLiquid crystalDensity functional theoryPhysical and Theoretical ChemistryPolymorphsdescription
Theoretical investigations concerning possible calcium sulfate, CaSO(4), high-pressure polymorphs have been carried out. Total-energy calculations and geometry optimizations have been performed by using density functional theory at the B3LYP level for all crystal structures considered. The following sequence of pressure-driven structural transitions has been found: anhydrite, Cmcm (in parentheses the transition pressure) → monazite-type, P2(1)/n (5 GPa) → barite-type, Pnma (8 GPa), and scheelite-type, I4(1)/a (8 GPa). The equation of state of the different polymorphs is determined, while their corresponding vibrational properties have been calculated and compared with previous theoretical results and experimental data.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2012-01-07 |