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DOE OSTI · 1274699

Materials Data on Ca14MnSb11 by Materials Project

Abstract

Ca14MnSb11 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional. there are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six Sb+2.73- atoms to form CaSb6 octahedra that share corners with four CaSb6 octahedra, corners with two equivalent MnSb4 tetrahedra, edges with two equivalent CaSb6 octahedra, and faces with two CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 38–55°. There are a spread of Ca–Sb bond distances ranging from 3.22–3.28 Å. In the second Ca2+ site, Ca2+ is bonded to six Sb+2.73- atoms to form CaSb6 octahedra that share corners with eight CaSb6 octahedra, corners with two equivalent MnSb4 tetrahedra, and faces with two equivalent CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 39–55°. There are a spread of Ca–Sb bond distances ranging from 3.16–3.38 Å. In the third Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six Sb+2.73- atoms. There are a spread of Ca–Sb bond distances ranging from 3.19–3.77 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six Sb+2.73- atoms. There are a spread of Ca–Sb bond distances ranging from 3.17–3.79 Å. Mn2+ is bonded to four equivalent Sb+2.73- atoms to form MnSb4 tetrahedra that share corners with twelve CaSb6 octahedra. The corner-sharing octahedra tilt angles range from 41–50°. All Mn–Sb bond lengths are 2.71 Å. There are four inequivalent Sb+2.73- sites. In the first Sb+2.73- site, Sb+2.73- is bonded in a 7-coordinate geometry to seven Ca2+ and one Mn2+ atom. In the second Sb+2.73- site, Sb+2.73- is bonded in a 10-coordinate geometry to eight Ca2+ atoms. In the third Sb+2.73- site, Sb+2.73- is bonded in a 7-coordinate geometry to eight Ca2+ atoms. In the fourth Sb+2.73- site, Sb+2.73- is bonded in a 8-coordinate geometry to eight Ca2+ atoms.

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2020-04-29. Materials Data on Ca14MnSb11 by Materials Project. https://doi.org/10.17188/1274699

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36 MATERIALS SCIENCE↗