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DOE OSTI · 1753307

Materials Data on Mn8Si8Mo3 by Materials Project

Abstract

Mo3Mn8Si8 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Mo+2.67+ sites. In the first Mo+2.67+ site, Mo+2.67+ is bonded to seven Si3- atoms to form MoSi7 pentagonal bipyramids that share corners with seven MoSi7 pentagonal bipyramids, corners with two equivalent MnSi6 pentagonal pyramids, an edgeedge with one MoSi7 pentagonal bipyramid, edges with two equivalent MnSi6 pentagonal pyramids, and faces with two equivalent MnSi6 pentagonal pyramids. There are a spread of Mo–Si bond distances ranging from 2.47–2.66 Å. In the second Mo+2.67+ site, Mo+2.67+ is bonded to seven Si3- atoms to form MoSi7 pentagonal bipyramids that share corners with four MoSi7 pentagonal bipyramids, corners with four MnSi6 pentagonal pyramids, edges with three MoSi7 pentagonal bipyramids, faces with two equivalent MoSi7 pentagonal bipyramids, and faces with two equivalent MnSi6 pentagonal pyramids. There are a spread of Mo–Si bond distances ranging from 2.45–2.67 Å. In the third Mo+2.67+ site, Mo+2.67+ is bonded to seven Si3- atoms to form MoSi7 pentagonal bipyramids that share corners with seven MoSi7 pentagonal bipyramids, edges with three equivalent MnSi6 pentagonal pyramids, faces with two equivalent MoSi7 pentagonal bipyramids, and a faceface with one MnSi6 pentagonal pyramid. There are a spread of Mo–Si bond distances ranging from 2.59–2.69 Å. There are six inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded in a 5-coordinate geometry to two equivalent Mn2+ and five Si3- atoms. There are one shorter (2.30 Å) and one longer (2.54 Å) Mn–Mn bond lengths. There are a spread of Mn–Si bond distances ranging from 2.38–2.40 Å. In the second Mn2+ site, Mn2+ is bonded in a 8-coordinate geometry to two equivalent Mn2+ and six Si3- atoms. There are one shorter (2.38 Å) and one longer (2.46 Å) Mn–Mn bond lengths. There are a spread of Mn–Si bond distances ranging from 2.44–2.53 Å. In the third Mn2+ site, Mn2+ is bonded to six Si3- atoms to form distorted MnSi6 pentagonal pyramids that share corners with three MoSi7 pentagonal bipyramids, corners with three MnSi6 pentagonal pyramids, edges with two equivalent MoSi7 pentagonal bipyramids, an edgeedge with one MnSi6 pentagonal pyramid, and faces with three MoSi7 pentagonal bipyramids. There are a spread of Mn–Si bond distances ranging from 2.32–2.58 Å. In the fourth Mn2+ site, Mn2+ is bonded in a 7-coordinate geometry to one Mn2+ and six Si3- atoms. The Mn–Mn bond length is 2.56 Å. There are a spread of Mn–Si bond distances ranging from 2.34–2.77 Å. In the fifth Mn2+ site, Mn2+ is bonded in a 7-coordinate geometry to one Mn2+ and six Si3- atoms. There are a spread of Mn–Si bond distances ranging from 2.42–2.72 Å. In the sixth Mn2+ site, Mn2+ is bonded to six Si3- atoms to form distorted MnSi6 pentagonal pyramids that share corners with three equivalent MoSi7 pentagonal bipyramids, corners with three MnSi6 pentagonal pyramids, edges with three equivalent MoSi7 pentagonal bipyramids, an edgeedge with one MnSi6 pentagonal pyramid, and faces with two equivalent MoSi7 pentagonal bipyramids. There are a spread of Mn–Si bond distances ranging from 2.32–2.58 Å. There are seven inequivalent Si3- sites. In the first Si3- site, Si3- is bonded in a 9-coordinate geometry to three Mo+2.67+, four Mn2+, and two equivalent Si3- atoms. There are one shorter (2.40 Å) and one longer (2.44 Å) Si–Si bond lengths. In the second Si3- site, Si3- is bonded in a 8-coordinate geometry to two Mo+2.67+ and six Mn2+ atoms. In the third Si3- site, Si3- is bonded in a 8-coordinate geometry to two Mo+2.67+ and six Mn2+ atoms. In the fourth Si3- site, Si3- is bonded in a 9-coordinate geometry to two equivalent Mo+2.67+ and seven Mn2+ atoms. In the fifth Si3- site, Si3- is bonded in a 9-coordinate geometry to four Mo+2.67+ and five Mn2+ atoms. In the sixth Si3- site, Si3- is bonded in a 10-coordinate geometry to two Mo+2.67+ and eight Mn2+ atoms. In the seventh Si3- site, Si3- is bonded in a 9-coordinate geometry to three Mo+2.67+ and six Mn2+ atoms.

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2020-06-04. Materials Data on Mn8Si8Mo3 by Materials Project. https://doi.org/10.17188/1753307

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