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RESEARCH PRODUCT
External pressure and composition effects on the atomic and electronic structure of SnWO4
Aleksandr KalinkoR. KalendarevJanis TimoshenkoAndris AnspoksAlexei Kuzminsubject
Absorption spectroscopyExtended X-ray absorption fine structureRenewable Energy Sustainability and the EnvironmentBand gapChemistryElectronic structureCrystal structureMolecular physicsSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsCrystallographyAtomic orbitalOctahedronLinear combination of atomic orbitalsddc:530description
The atomic and electronic structure of tin tungstates, α-SnWO4, α-Sn1.03W0.99O4 and β-SnWO4 ,w as studied by the W L3-edge X-ray absorption spectroscopy and first-principles linear combination of atomic orbital (LCAO) calculations based on the hybrid exchange-correlation density functional (DFT)/ Hartree–Fock (HF) scheme. It was found that the crystal structure of both α-phases is built up of strongly distorted WO6 octahedra, whereas that of β-SnWO4 is composed of nearly regular WO4 tetrahedra. In addition, there are distorted SnO6 octahedra in both α- and β-phases. The metal–oxygen octahedra distortion is explained by the second-order Jahn–Teller effect. The influence of pressure on the structure of α-SnWO4 and β-SnWO4 was studied in detail based on the calculated equations of state. The compressibility of β-SnWO4 was found to be larger than that of α-SnWO4. The existence of the insulatorto-metal transition was theoretically predicted in α-SnWO4 at about 16 GPa and was explained by a symmetrization of metal–oxygen octahedra leading to a strong interaction of Sn 5s ,W5 d and O 2p states and closing of band gap.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2015-12-01 |