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DOE OSTI · 1274799

Materials Data on KTh(SbSe3)2 by Materials Project

Abstract

KTh(SbSe3)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. K1+ is bonded in a 9-coordinate geometry to nine Se+1.83- atoms. There are a spread of K–Se bond distances ranging from 3.32–3.86 Å. Th4+ is bonded in a 9-coordinate geometry to nine Se+1.83- atoms. There are a spread of Th–Se bond distances ranging from 2.97–3.20 Å. There are two inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded to six Se+1.83- atoms to form a mixture of distorted corner and edge-sharing SbSe6 octahedra. The corner-sharing octahedra tilt angles range from 9–10°. There are a spread of Sb–Se bond distances ranging from 2.67–3.38 Å. In the second Sb3+ site, Sb3+ is bonded to six Se+1.83- atoms to form a mixture of corner and edge-sharing SbSe6 octahedra. The corner-sharing octahedra tilt angles range from 9–10°. There are a spread of Sb–Se bond distances ranging from 2.67–3.29 Å. There are six inequivalent Se+1.83- sites. In the first Se+1.83- site, Se+1.83- is bonded in a 4-coordinate geometry to two equivalent K1+, one Th4+, and two equivalent Sb3+ atoms. In the second Se+1.83- site, Se+1.83- is bonded in a 5-coordinate geometry to one K1+, one Th4+, and three Sb3+ atoms. In the third Se+1.83- site, Se+1.83- is bonded to one K1+ and five Sb3+ atoms to form distorted SeKSb5 octahedra that share edges with four equivalent SeKSb5 octahedra and edges with two equivalent SeK2Th2Sb square pyramids. In the fourth Se+1.83- site, Se+1.83- is bonded in a 5-coordinate geometry to two equivalent K1+, two equivalent Th4+, and one Sb3+ atom. In the fifth Se+1.83- site, Se+1.83- is bonded in a 5-coordinate geometry to one K1+, three equivalent Th4+, and one Se+1.83- atom. The Se–Se bond length is 2.54 Å. In the sixth Se+1.83- site, Se+1.83- is bonded to two equivalent K1+, two equivalent Th4+, and one Sb3+ atom to form distorted SeK2Th2Sb square pyramids that share edges with two equivalent SeKSb5 octahedra and edges with two equivalent SeK2Th2Sb square pyramids.

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2020-07-15. Materials Data on KTh(SbSe3)2 by Materials Project. https://doi.org/10.17188/1274799

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