High-pressure structural study of the scheelite tungstates CaWO{sub 4} and SrWO{sub 4}

Journal Article · Tue Nov 01 04:00:00 EST 2005 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.72.174106· OSTI ID:20719777

Errandonea, D; Pellicer-Porres, J; Segura, A; Ferrer-Roca, Ch ^[1]; Manjon, F J ^[2]; Kumar, R S; Tschauner, O ^[3]; Rodriguez-Hernandez, P; Lopez-Solano, J; Radescu, S; Mujica, A; Munoz, A ^[4]; Aquilanti, G ^[5]

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1. Departamento de Fisica Aplicada-ICMUV, Universitat de Valencia, Edificio de Investigacion, c/Dr. Moliner 50, 46100 Burjassot, Valencia (Spain)
2. Departamento de Fisica Aplicada, Universitat Politecnica de Valencia, Cno. de Vera s/n, 46022 Valencia (Spain)
3. High Pressure Science and Engineering Center, Department of Physics, University of Nevada, 4505 Maryland Parkway, Las Vegas, Nevada 89154-4002 (United States)
4. Departamento de Fisica Fundamental II, Universidad de La Laguna, La Laguna 38205, Tenerife (Spain)
5. European Synchrotron Radiation Facility, BP 220, Grenoble, F-38043 (France)

Angle-dispersive x-ray-diffraction and x-ray-absorption near-edge structure measurements have been performed on CaWO{sub 4} and SrWO{sub 4} up to pressures of approximately 20 GPa. Both materials display similar behavior in the range of pressures investigated in our experiments. As in the previously reported case of CaWO{sub 4}, under hydrostatic conditions SrWO{sub 4} undergoes a pressure-induced scheelite-to-fergusonite transition around 10 GPa. Our experimental results are compared to those found in the literature and are further supported by ab initio total-energy calculations, from which we also predict the instability at larger pressures of the fergusonite phases against an orthorhombic structure with space group Cmca. Finally, a linear relationship between the charge density in the AO{sub 8} polyhedra of ABO{sub 4} scheelite-related structures and their bulk modulus is discussed and used to predict the bulk modulus of other materials, like hafnon.

• OSTI ID: 20719777
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 17 Vol. 72; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION SPECTROSCOPY
CALCIUM TUNGSTATES
CHARGE DENSITY
ORTHORHOMBIC LATTICES
PHASE TRANSFORMATIONS
PRESSURE DEPENDENCE
PRESSURE RANGE GIGA PA
SPACE GROUPS
STRONTIUM COMPOUNDS
X RADIATION
X-RAY DIFFRACTION
X-RAY SPECTROSCOPY