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DOE OSTI · 1651690

Materials Data on Mg6TiSi by Materials Project

Abstract

Mg6TiSi crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to eight Mg, two equivalent Ti, and two equivalent Si atoms to form distorted MgMg8Ti2Si2 cuboctahedra that share corners with four equivalent TiMg10Si2 cuboctahedra, corners with fourteen MgMg8Ti2Si2 cuboctahedra, edges with two equivalent TiMg10Si2 cuboctahedra, edges with eight MgMg8Ti2Si2 cuboctahedra, faces with two equivalent TiMg10Si2 cuboctahedra, and faces with eight MgMg8Ti2Si2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.01–3.19 Å. There are one shorter (2.99 Å) and one longer (3.23 Å) Mg–Ti bond lengths. Both Mg–Si bond lengths are 3.05 Å. In the second Mg site, Mg is bonded to ten Mg and two equivalent Ti atoms to form MgMg10Ti2 cuboctahedra that share corners with four equivalent TiMg10Si2 cuboctahedra, corners with fourteen MgMg8Ti2Si2 cuboctahedra, edges with two equivalent TiMg10Si2 cuboctahedra, edges with eight MgMg8Ti2Si2 cuboctahedra, faces with two equivalent TiMg10Si2 cuboctahedra, and faces with eight MgMg8Ti2Si2 cuboctahedra. There are two shorter (2.98 Å) and four longer (3.00 Å) Mg–Mg bond lengths. Both Mg–Ti bond lengths are 3.15 Å. In the third Mg site, Mg is bonded in a 12-coordinate geometry to six Mg, two equivalent Ti, and one Si atom. There are one shorter (3.08 Å) and one longer (3.13 Å) Mg–Mg bond lengths. Both Mg–Ti bond lengths are 3.02 Å. The Mg–Si bond length is 2.90 Å. In the fourth Mg site, Mg is bonded to ten Mg and two equivalent Si atoms to form distorted MgMg10Si2 cuboctahedra that share corners with six equivalent MgMg10Si2 cuboctahedra, edges with twelve MgMg8Ti2Si2 cuboctahedra, faces with six equivalent TiMg10Si2 cuboctahedra, and faces with eight MgMg8Ti2Si2 cuboctahedra. Both Mg–Si bond lengths are 3.15 Å. Ti is bonded to ten Mg and two equivalent Si atoms to form TiMg10Si2 cuboctahedra that share corners with six equivalent TiMg10Si2 cuboctahedra, corners with twelve MgMg8Ti2Si2 cuboctahedra, edges with six MgMg8Ti2Si2 cuboctahedra, faces with two equivalent TiMg10Si2 cuboctahedra, and faces with twelve MgMg8Ti2Si2 cuboctahedra. Both Ti–Si bond lengths are 2.81 Å. Si is bonded in a 12-coordinate geometry to eight Mg and two equivalent Ti atoms.

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2019-10-22. Materials Data on Mg6TiSi by Materials Project. https://doi.org/10.17188/1651690

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