Search results for "Pressure effects"

showing 2 items of 2 documents

High-pressure theoretical and experimental study of HgWO4

2011

HgWO 4 at ambient pressure is characterized using a combination of ab initio calculations, X-ray diffraction and Raman scattering measurements. The effect of low pressure and temperature on the structural stability is analysed. Extending our ab initio study to the range of higher pressures, a sequence of stable phases up to 30GPa is proposed. © 2011 Taylor & Francis.

DiffractionRaman scatteringLow pressuresX ray diffractionAb initioExperimental studiesPressure effectsMolecular physicsStable phasisScatteringCondensed Matter::Materials Sciencesymbols.namesakeAb initio quantum chemistry methodsX raysScatteringChemistryRaman Scattering measurementsTungstatesCondensed Matter PhysicsX-ray diffractionAmbient pressuresAb initio studyStructural stabilityPhase transitionsFISICA APLICADAX-ray crystallographysymbolsStructural stabilitiesTungsten compoundsAb initio calculationsCalculationsDiffractionStabilityRaman scatteringAmbient pressure
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X-ray diffraction measurements of Mo melting to 119 GPa and the high pressure phase diagram

2009

In this paper, we report angle-dispersive X-ray diffraction data of molybdenum melting, measured in a double-sided laser-heated diamond-anvil cell up to a pressure of 119 GPa and temperatures up to 3400 K. The new melting temperatures are in excellent agreement with earlier measurements up to 90 GPa that relied on optical observations of melting and in strong contrast to most theoretical estimates. The X-ray measurements show that the solid melts from the bcc structure throughout the reported pressure range and provide no evidence for a high temperature transition from bcc to a close-packed structure, or to any other crystalline structure. This observation contradicts earlier interpretation…

MolybdenumShock wave effectsDiffractionMaterials scienceShock (fluid dynamics)General Physics and Astronomychemistry.chemical_elementThermodynamicsMeltingCrystal structureAcoustic wave velocity ; High-pressure effects ; Melting ; Molybdenum ; Phase diagrams ; Shock wave effects ; X-ray diffractionX-ray diffractionUNESCO::FÍSICA::Química físicaHigh-pressure effectsCrystallographychemistryAcoustic wave velocityMolybdenumSpeed of soundHigh pressureX-ray crystallographyPhase diagramsPhysical and Theoretical Chemistry:FÍSICA::Química física [UNESCO]Phase diagram
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