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DOE OSTI · 1759239

Materials Data on CsNd2Ag3Te5 by Materials Project

Abstract

CsNd2Ag3Te5 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 3.86–3.94 Å. Nd3+ is bonded to six Te2- atoms to form NdTe6 octahedra that share a cornercorner with one NdTe6 octahedra, corners with four equivalent AgTe4 tetrahedra, edges with four equivalent NdTe6 octahedra, and edges with five AgTe4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. There are a spread of Nd–Te bond distances ranging from 3.16–3.26 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 NdTe6 octahedra. There are two shorter (2.80 Å) and two longer (2.97 Å) Ag–Te bond lengths. In the second Ag1+ site, Ag1+ is bonded to four Te2- atoms to form distorted AgTe4 tetrahedra that share corners with four equivalent NdTe6 octahedra, corners with four AgTe4 tetrahedra, edges with three equivalent NdTe6 octahedra, and an edgeedge with one AgTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 15–63°. There are a spread of Ag–Te bond distances ranging from 2.86–2.95 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 Nd3+, and two equivalent Ag1+ atoms. In the second Te2- site, Te2- is bonded in a 7-coordinate geometry to two equivalent Cs1+, two equivalent Nd3+, and three Ag1+ atoms. In the third Te2- site, Te2- is bonded to one Cs1+, three equivalent Nd3+, and two equivalent Ag1+ atoms to form a mixture of distorted corner and edge-sharing TeCsNd3Ag2 octahedra. The corner-sharing octahedral tilt angles are 59°.

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2020-09-03. Materials Data on CsNd2Ag3Te5 by Materials Project. https://doi.org/10.17188/1759239

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36 MATERIALS SCIENCE↗