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DOE OSTI · 1730234

Materials Data on Mn2SiMo by Materials Project

Abstract

MoMn2Si is Bergman Structure: Mg32(Al,Zn)49 Bergman-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are three inequivalent Mo sites. In the first Mo site, Mo is bonded in a 1-coordinate geometry to one Mo, eight Mn, and six Si atoms. The Mo–Mo bond length is 2.89 Å. There are a spread of Mo–Mn bond distances ranging from 2.47–2.92 Å. There are a spread of Mo–Si bond distances ranging from 2.79–2.85 Å. In the second Mo site, Mo is bonded in a 12-coordinate geometry to four Mo, eight Mn, and four equivalent Si atoms. There are two shorter (2.87 Å) and one longer (2.89 Å) Mo–Mo bond lengths. There are a spread of Mo–Mn bond distances ranging from 2.73–2.88 Å. There are two shorter (2.68 Å) and two longer (2.71 Å) Mo–Si bond lengths. In the third Mo site, Mo is bonded in a 1-coordinate geometry to three equivalent Mo, ten Mn, and three Si atoms. There are a spread of Mo–Mn bond distances ranging from 2.62–2.89 Å. There are one shorter (2.68 Å) and two longer (2.69 Å) Mo–Si bond lengths. There are five inequivalent Mn sites. In the first Mn site, Mn is bonded to three equivalent Mo, four Mn, and five Si atoms to form distorted MnMn4Si5Mo3 cuboctahedra that share corners with six MnMn6Si2Mo4 cuboctahedra, edges with six equivalent MnMn4Si5Mo3 cuboctahedra, and faces with eleven MnMn4Si2Mo6 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.30–2.45 Å. There are a spread of Mn–Si bond distances ranging from 2.45–2.85 Å. In the second Mn site, Mn is bonded to six Mo, four Mn, and two equivalent Si atoms to form distorted MnMn4Si2Mo6 cuboctahedra that share corners with six MnMn6Si2Mo4 cuboctahedra, edges with six equivalent MnMn4Si2Mo6 cuboctahedra, and faces with eleven MnMn4Si5Mo3 cuboctahedra. There are a spread of Mn–Mn bond distances ranging from 2.37–2.52 Å. Both Mn–Si bond lengths are 2.36 Å. In the third Mn site, Mn is bonded to four Mo, six Mn, and two equivalent Si atoms to form MnMn6Si2Mo4 cuboctahedra that share corners with eight MnMn4Si5Mo3 cuboctahedra, edges with two equivalent MnMn6Si2Mo4 cuboctahedra, and faces with fourteen MnMn4Si5Mo3 cuboctahedra. There are two shorter (2.26 Å) and two longer (2.40 Å) Mn–Mn bond lengths. Both Mn–Si bond lengths are 2.68 Å. In the fourth Mn site, Mn is bonded to four Mo, six Mn, and two equivalent Si atoms to form MnMn6Si2Mo4 cuboctahedra that share corners with eight MnMn4Si5Mo3 cuboctahedra, edges with two equivalent MnMn6Si2Mo4 cuboctahedra, and faces with fourteen MnMn4Si5Mo3 cuboctahedra. There are one shorter (2.28 Å) and one longer (2.48 Å) Mn–Mn bond lengths. There are one shorter (2.60 Å) and one longer (2.62 Å) Mn–Si bond lengths. In the fifth Mn site, Mn is bonded in a 12-coordinate geometry to five Mo, two Mn, and five Si atoms. There are a spread of Mn–Si bond distances ranging from 2.31–2.67 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 11-coordinate geometry to five Mo, four Mn, and two equivalent Si atoms. There are one shorter (2.36 Å) and one longer (2.40 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 9-coordinate geometry to three Mo and ten Mn atoms.

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2020-05-02. Materials Data on Mn2SiMo by Materials Project. https://doi.org/10.17188/1730234

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