6533b831fe1ef96bd12986f6
RESEARCH PRODUCT
Polymorphism in Strontium Tungstate SrWO 4 under Quasi-Hydrostatic Compression
David Santamaría-pérezR. Lacomba-peralesDaniel ErrandoneaAlfonso MunozAlain PolianPlácida Rodríguez-hernándezYue Mengsubject
Diffraction[PHYS]Physics [physics]02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesInorganic Chemistrychemistry.chemical_compoundsymbols.namesakeCrystallographyTetragonal crystal systemTungstatechemistryPolymorphism (materials science)Ab initio quantum chemistry methods0103 physical sciencessymbolsOrthorhombic crystal systemPhysical and Theoretical Chemistry010306 general physics0210 nano-technologyRaman spectroscopyComputingMilieux_MISCELLANEOUSMonoclinic crystal systemdescription
The structural and vibrational properties of SrWO4 have been studied experimentally up to 27 and 46 GPa, respectively, by angle-dispersive synchrotron X-ray diffraction and Raman spectroscopy measurements as well as using ab initio calculations. The existence of four polymorphs upon quasi-hydrostatic compression is reported. The three phase transitions were found at 11.5, 19.0, and 39.5 GPa. The ambient-pressure SrWO4 tetragonal scheelite-type structure (S.G. I41/a) undergoes a transition to a monoclinic fergusonite-type structure (S.G. I2/a) at 11.5 GPa with a 1.5% volume decrease. Subsequently, at 19.0 GPa, another structural transformation takes place. Our calculations indicate two possible post-fergusonite phases, one monoclinic and the other orthorhombic. In the diffraction experiments, we observed the theoretically predicted monoclinic LaTaO4-type phase coexisting with the fergusonite-type phase up to 27 GPa. The coexistence of the two phases and the large volume collapse at the transition confirm a...
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2016-09-28 |