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DOE OSTI · 1204232

Materials Data on Na3(Mn2Te3)2 by Materials Project

Abstract

Na3(Mn2Te3)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six Te2- atoms to form NaTe6 octahedra that share corners with eight equivalent MnTe4 tetrahedra, edges with six NaTe6 octahedra, and edges with four equivalent MnTe4 tetrahedra. There are a spread of Na–Te bond distances ranging from 3.21–3.36 Å. In the second Na1+ site, Na1+ is bonded to six Te2- atoms to form NaTe6 octahedra that share corners with eight equivalent MnTe4 tetrahedra, edges with six equivalent NaTe6 octahedra, and edges with four equivalent MnTe4 tetrahedra. There are two shorter (3.18 Å) and four longer (3.39 Å) Na–Te bond lengths. Mn+2.25+ is bonded to four Te2- atoms to form MnTe4 tetrahedra that share corners with six NaTe6 octahedra, corners with three equivalent MnTe4 tetrahedra, edges with three NaTe6 octahedra, and edges with two equivalent MnTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 18–57°. There are a spread of Mn–Te bond distances ranging from 2.66–2.76 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to three Na1+ and two equivalent Mn+2.25+ atoms to form TeNa3Mn2 square pyramids that share corners with six equivalent TeNa3Mn3 pentagonal pyramids, a cornercorner with one TeNa3Mn2 square pyramid, edges with six equivalent TeNa3Mn3 pentagonal pyramids, and an edgeedge with one TeNa3Mn2 square pyramid. In the second Te2- site, Te2- is bonded to three Na1+ and three equivalent Mn+2.25+ atoms to form distorted TeNa3Mn3 pentagonal pyramids that share corners with three equivalent TeNa3Mn3 pentagonal pyramids, corners with three equivalent TeNa3Mn2 square pyramids, edges with six equivalent TeNa3Mn3 pentagonal pyramids, and edges with three equivalent TeNa3Mn2 square pyramids.

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2020-07-14. Materials Data on Na3(Mn2Te3)2 by Materials Project. https://doi.org/10.17188/1204232

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36 MATERIALS SCIENCE↗