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DOE OSTI · 1746420

Materials Data on MgTi by Materials Project

Abstract

MgTi is beta-derived structured and crystallizes in the orthorhombic Pmmn space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to ten Mg and two equivalent Ti atoms to form MgMg10Ti2 cuboctahedra that share corners with eight TiMg2Ti10 cuboctahedra, corners with ten MgMg10Ti2 cuboctahedra, edges with six MgMg10Ti2 cuboctahedra, edges with twelve TiMg2Ti10 cuboctahedra, faces with four equivalent TiMg6Ti6 cuboctahedra, and faces with sixteen MgMg10Ti2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.96–3.27 Å. Both Mg–Ti bond lengths are 3.19 Å. In the second Mg site, Mg is bonded to six Mg and six Ti atoms to form distorted MgMg6Ti6 cuboctahedra that share corners with eight TiMg2Ti10 cuboctahedra, corners with ten MgMg10Ti2 cuboctahedra, edges with six MgMg10Ti2 cuboctahedra, edges with twelve TiMg2Ti10 cuboctahedra, faces with eight TiMg2Ti10 cuboctahedra, and faces with twelve MgMg10Ti2 cuboctahedra. Both Mg–Mg bond lengths are 2.96 Å. There are four shorter (3.07 Å) and two longer (3.08 Å) Mg–Ti bond lengths. There are two inequivalent Ti sites. In the first Ti site, Ti is bonded to two equivalent Mg and ten Ti atoms to form TiMg2Ti10 cuboctahedra that share corners with eight MgMg10Ti2 cuboctahedra, corners with ten TiMg2Ti10 cuboctahedra, edges with six TiMg2Ti10 cuboctahedra, edges with twelve MgMg10Ti2 cuboctahedra, faces with four equivalent MgMg6Ti6 cuboctahedra, and faces with sixteen TiMg2Ti10 cuboctahedra. There are a spread of Ti–Ti bond distances ranging from 2.78–2.96 Å. In the second Ti site, Ti is bonded to six Mg and six Ti atoms to form TiMg6Ti6 cuboctahedra that share corners with eight MgMg10Ti2 cuboctahedra, corners with ten TiMg2Ti10 cuboctahedra, edges with six TiMg2Ti10 cuboctahedra, edges with twelve MgMg10Ti2 cuboctahedra, faces with eight MgMg10Ti2 cuboctahedra, and faces with twelve TiMg2Ti10 cuboctahedra. Both Ti–Ti bond lengths are 2.96 Å.

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2020-05-02. Materials Data on MgTi by Materials Project. https://doi.org/10.17188/1746420

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