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DOE OSTI · 1758949

Materials Data on NbTlWO6 by Materials Project

Abstract

TlNbWO6 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra, corners with four equivalent WO6 octahedra, and corners with six equivalent TlO6 octahedra. The corner-sharing octahedra tilt angles range from 39–72°. There are two shorter (1.99 Å) and four longer (2.01 Å) Nb–O bond lengths. W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent WO6 octahedra, corners with four equivalent NbO6 octahedra, and corners with six equivalent TlO6 octahedra. The corner-sharing octahedra tilt angles range from 37–71°. There is four shorter (1.93 Å) and two longer (1.95 Å) W–O bond length. Tl1+ is bonded to six O2- atoms to form TlO6 octahedra that share corners with six equivalent NbO6 octahedra and corners with six equivalent WO6 octahedra. The corner-sharing octahedra tilt angles range from 69–72°. There are a spread of Tl–O bond distances ranging from 3.26–3.34 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent W6+ and one Tl1+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Nb5+ and one Tl1+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Nb5+, one W6+, and one Tl1+ atom.

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2020-09-03. Materials Data on NbTlWO6 by Materials Project. https://doi.org/10.17188/1758949

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36 MATERIALS SCIENCE↗