6533b82efe1ef96bd129333a
RESEARCH PRODUCT
New high-pressure phase and equation of state of Ce2Zr2O8
Rakesh ShuklaRavhi S. KumarD. ErrandoneaOscar GomisAdish TyagiS. N. AcharyFrancisco Javier Manjónsubject
powdersEquation of statePhase transitionMaterials scienceFOS: Physical sciencesGeneral Physics and AstronomyThermodynamicsCrystal structurePressure coefficientCondensed Matter::Materials Sciencesymbols.namesakefluoritePhase (matter)OxidationCondensed Matter - Materials ScienceRietveld refinementCrystal structureEquations of stateMaterials Science (cond-mat.mtrl-sci)phase transitionshigh pressurex-ray diffractionFISICA APLICADACompressibilitysymbolsraman spectraRaman spectroscopyrietveld refinementdescription
In this paper we report a new high-pressure rhombohedral phase of Ce2Zr2O8 observed from high-pressure angle-dispersive x-ray diffraction and Raman spectroscopy studies up to nearly 12 GPa. The ambient-pressure cubic phase of Ce2Zr2O8 transforms to a rhombohedral structure beyond 5 GPa with a feeble distortion in the lattice. Pressure evolution of unit-cell volume showed a change in compressibility above 5 GPa. The unit-cell parameters of the high-pressure rhombohedral phase at 12.1 GPa are ah = 14.6791(3) {\AA}, ch = 17.9421(5) {\AA}, V = 3348.1(1) {\AA}3. The structure relation between the parent cubic (P2_13) and rhombohedral (P3_2) phases were obtained by group-subgroup relations. All the Raman modes of the cubic phase showed linear evolution with pressure with the hardest one at 197 cm-1. Some Raman modes of the high-pressure phase have a non-linear evolution with pressure and softening of one low-frequency mode with pressure is found. The compressibility, equation of state, and pressure coefficients of Raman modes of Ce2Zr2O8 are also reported.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2012-01-01 |