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DOE OSTI · 1725589

Materials Data on CsGd2Ag3Te5 by Materials Project

Abstract

CsGd2Ag3Te5 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Cs1+ is bonded in a 8-coordinate geometry to eight Te2- atoms. There are a spread of Cs–Te bond distances ranging from 3.87–3.99 Å. Gd3+ is bonded to six Te2- atoms to form GdTe6 octahedra that share a cornercorner with one GdTe6 octahedra, corners with four equivalent AgAgTe4 tetrahedra, edges with four equivalent GdTe6 octahedra, and edges with five AgTe4 tetrahedra. The corner-sharing octahedral tilt angles are 37°. There are a spread of Gd–Te bond distances ranging from 3.11–3.19 Å. There are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to four Te2- atoms to form AgTe4 tetrahedra that share corners with six AgTe4 tetrahedra and edges with four equivalent GdTe6 octahedra. There are two shorter (2.83 Å) and two longer (2.91 Å) Ag–Te bond lengths. In the second Ag1+ site, Ag1+ is bonded to one Ag1+ and four Te2- atoms to form distorted AgAgTe4 tetrahedra that share corners with two equivalent TeCsGd3Ag2 octahedra, corners with four equivalent GdTe6 octahedra, corners with four AgTe4 tetrahedra, edges with three equivalent GdTe6 octahedra, and an edgeedge with one AgAgTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 10–62°. The Ag–Ag bond length is 3.01 Å. There are a spread of Ag–Te bond distances ranging from 2.88–2.92 Å. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 6-coordinate geometry to two equivalent Cs1+, two equivalent Gd3+, and two equivalent Ag1+ atoms. In the second Te2- site, Te2- is bonded in a 7-coordinate geometry to two equivalent Cs1+, two equivalent Gd3+, and three Ag1+ atoms. In the third Te2- site, Te2- is bonded to one Cs1+, three equivalent Gd3+, and two equivalent Ag1+ atoms to form distorted TeCsGd3Ag2 octahedra that share a cornercorner with one TeCsGd3Ag2 octahedra, corners with two equivalent AgAgTe4 tetrahedra, and edges with four equivalent TeCsGd3Ag2 octahedra. The corner-sharing octahedral tilt angles are 60°.

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2020-05-03. Materials Data on CsGd2Ag3Te5 by Materials Project. https://doi.org/10.17188/1725589

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36 MATERIALS SCIENCE↗