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DOE OSTI · 1187117

Materials Data on K2UTe3 by Materials Project

Abstract

K2UTe3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six Te2- atoms to form distorted KTe6 octahedra that share corners with two equivalent KTe6 octahedra, corners with four equivalent UTe6 octahedra, edges with four equivalent UTe6 octahedra, and edges with eight KTe6 octahedra. The corner-sharing octahedra tilt angles range from 12–13°. There are a spread of K–Te bond distances ranging from 3.45–3.75 Å. In the second K1+ site, K1+ is bonded to six Te2- atoms to form KTe6 octahedra that share corners with two equivalent KTe6 octahedra, corners with four equivalent UTe6 octahedra, edges with four equivalent UTe6 octahedra, and edges with eight KTe6 octahedra. The corner-sharing octahedra tilt angles range from 11–15°. There are two shorter (3.40 Å) and four longer (3.70 Å) K–Te bond lengths. In the third K1+ site, K1+ is bonded to six Te2- atoms to form KTe6 octahedra that share corners with six KTe6 octahedra, edges with six KTe6 octahedra, and edges with six equivalent UTe6 octahedra. The corner-sharing octahedra tilt angles range from 13–15°. There are two shorter (3.45 Å) and four longer (3.49 Å) K–Te bond lengths. U4+ is bonded to six Te2- atoms to form UTe6 octahedra that share corners with six KTe6 octahedra, edges with three equivalent UTe6 octahedra, and edges with nine KTe6 octahedra. The corner-sharing octahedra tilt angles range from 11–13°. There are four shorter (3.09 Å) and two longer (3.10 Å) U–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to four K1+ and two equivalent U4+ atoms to form a mixture of edge and corner-sharing TeK4U2 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the second Te2- site, Te2- is bonded to four K1+ and two equivalent U4+ atoms to form a mixture of edge and corner-sharing TeK4U2 octahedra. The corner-sharing octahedra tilt angles range from 0–13°.

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2020-07-17. Materials Data on K2UTe3 by Materials Project. https://doi.org/10.17188/1187117

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36 MATERIALS SCIENCE↗