Extended X-Ray Absorption Fine Structure Spectroscopy and First-Principles Study of Snwo4

The local atomic structure in alpha- and beta-SnWO4 was studied by synchrotron radiation W L-3-edge x-ray absorption spectroscopy at 10 and 300 K. Strongly distorted WO6 octahedra were found in alpha-SnWO4, whereas nearly regular WO4 tetrahedra were observed in alpha-SnWO4, confirming previous results. The structural results obtained were supported by the first-principles calculations, suggesting that the second-order Jahn-Teller effect is responsible for octahedral distortion.