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DOE OSTI · 1280960

Materials Data on Mn14Si23 by Materials Project

Abstract

Mn14Si23 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. there are seven inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded in a 10-coordinate geometry to ten Si+1.22- atoms. There are a spread of Mn–Si bond distances ranging from 2.64–2.94 Å. In the second Mn2+ site, Mn2+ is bonded in a 11-coordinate geometry to eleven Si+1.22- atoms. There are a spread of Mn–Si bond distances ranging from 2.54–3.06 Å. In the third Mn2+ site, Mn2+ is bonded in a 1-coordinate geometry to one Mn2+ and ten Si+1.22- atoms. The Mn–Mn bond length is 2.52 Å. There are a spread of Mn–Si bond distances ranging from 2.34–2.96 Å. In the fourth Mn2+ site, Mn2+ is bonded in a 8-coordinate geometry to eight Si+1.22- atoms. There are a spread of Mn–Si bond distances ranging from 2.28–2.50 Å. In the fifth Mn2+ site, Mn2+ is bonded in a 10-coordinate geometry to ten Si+1.22- atoms. There are a spread of Mn–Si bond distances ranging from 2.44–2.96 Å. In the sixth Mn2+ site, Mn2+ is bonded in a 5-coordinate geometry to seven Si+1.22- atoms. There are a spread of Mn–Si bond distances ranging from 2.21–2.80 Å. In the seventh Mn2+ site, Mn2+ is bonded to one Mn2+ and six Si+1.22- atoms to form distorted corner-sharing MnMnSi6 hexagonal pyramids. The Mn–Mn bond length is 2.18 Å. There are a spread of Mn–Si bond distances ranging from 2.42–2.50 Å. There are nine inequivalent Si+1.22- sites. In the first Si+1.22- site, Si+1.22- is bonded in a 4-coordinate geometry to four Mn2+ and six Si+1.22- atoms. There are a spread of Si–Si bond distances ranging from 2.39–2.49 Å. In the second Si+1.22- site, Si+1.22- is bonded in a 10-coordinate geometry to five Mn2+ and five Si+1.22- atoms. There are a spread of Si–Si bond distances ranging from 2.41–2.69 Å. In the third Si+1.22- site, Si+1.22- is bonded in a 11-coordinate geometry to six Mn2+ and five Si+1.22- atoms. There are two shorter (2.41 Å) and two longer (2.58 Å) Si–Si bond lengths. In the fourth Si+1.22- site, Si+1.22- is bonded in a distorted bent 150 degrees geometry to six Mn2+ and five Si+1.22- atoms. There are one shorter (2.56 Å) and two longer (2.68 Å) Si–Si bond lengths. In the fifth Si+1.22- site, Si+1.22- is bonded to six Mn2+ and six Si+1.22- atoms to form edge-sharing SiMn6Si6 cuboctahedra. All Si–Si bond lengths are 2.39 Å. In the sixth Si+1.22- site, Si+1.22- is bonded in a distorted single-bond geometry to five Mn2+ and four Si+1.22- atoms. Both Si–Si bond lengths are 2.70 Å. In the seventh Si+1.22- site, Si+1.22- is bonded in a 12-coordinate geometry to six Mn2+ and six Si+1.22- atoms. There are a spread of Si–Si bond distances ranging from 2.33–2.66 Å. In the eighth Si+1.22- site, Si+1.22- is bonded in a 2-coordinate geometry to six Mn2+ and four Si+1.22- atoms. Both Si–Si bond lengths are 2.39 Å. In the ninth Si+1.22- site, Si+1.22- is bonded in a 11-coordinate geometry to five Mn2+ and six Si+1.22- atoms. There are one shorter (2.27 Å) and one longer (2.72 Å) Si–Si bond lengths.

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2020-05-02. Materials Data on Mn14Si23 by Materials Project. https://doi.org/10.17188/1280960

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36 MATERIALS SCIENCE↗