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DOE OSTI · 1191755

Materials Data on Cd2Sb2O7 by Materials Project

Abstract

Cd2Sb2O7 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. there are two inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.43 Å) and four longer (2.74 Å) Cd–O bond lengths. In the second Cd2+ site, Cd2+ is bonded to eight O2- atoms to form distorted CdO8 hexagonal bipyramids that share corners with two equivalent CdO8 hexagonal bipyramids, corners with two equivalent SbO6 octahedra, and edges with six SbO6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are a spread of Cd–O bond distances ranging from 2.22–2.83 Å. There are two inequivalent Sb5+ sites. In the first Sb5+ site, Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with six SbO6 octahedra and edges with four equivalent CdO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 44–45°. There is two shorter (1.98 Å) and four longer (1.99 Å) Sb–O bond length. In the second Sb5+ site, Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with two equivalent CdO8 hexagonal bipyramids, corners with four equivalent SbO6 octahedra, and edges with two equivalent CdO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 45°. There are four shorter (2.01 Å) and two longer (2.04 Å) Sb–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Cd2+ and two Sb5+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Cd2+ and two equivalent Sb5+ atoms. In the third O2- site, O2- is bonded to three Cd2+ and one Sb5+ atom to form a mixture of distorted edge and corner-sharing OCd3Sb tetrahedra.

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2020-07-15. Materials Data on Cd2Sb2O7 by Materials Project. https://doi.org/10.17188/1191755

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36 MATERIALS SCIENCE↗