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DOE OSTI · 1716485

Materials Data on Mg2Ti by Materials Project

Abstract

Mg2Ti is beta-derived structured and crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are eight inequivalent Mg sites. In the first Mg site, Mg is bonded to eight Mg and four Ti atoms to form distorted MgMg8Ti4 cuboctahedra that share corners with eight TiMg8Ti4 cuboctahedra, corners with ten MgMg8Ti4 cuboctahedra, edges with seven TiMg8Ti4 cuboctahedra, edges with eleven MgMg8Ti4 cuboctahedra, faces with six TiMg8Ti4 cuboctahedra, and faces with fourteen MgMg8Ti4 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.04–3.24 Å. There are a spread of Mg–Ti bond distances ranging from 3.08–3.39 Å. In the second Mg site, Mg is bonded to eight Mg and four Ti atoms to form distorted MgMg8Ti4 cuboctahedra that share corners with six TiMg8Ti4 cuboctahedra, corners with twelve MgMg8Ti4 cuboctahedra, edges with eight MgMg8Ti4 cuboctahedra, edges with ten TiMg8Ti4 cuboctahedra, faces with six TiMg8Ti4 cuboctahedra, and faces with fourteen MgMg8Ti4 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.02–3.25 Å. There are a spread of Mg–Ti bond distances ranging from 3.08–3.37 Å. In the third Mg site, Mg is bonded to ten Mg and two Ti atoms to form MgMg10Ti2 cuboctahedra that share corners with seven TiMg8Ti4 cuboctahedra, corners with eleven MgMg8Ti4 cuboctahedra, edges with nine MgMg8Ti4 cuboctahedra, edges with nine TiMg8Ti4 cuboctahedra, faces with four TiMg8Ti4 cuboctahedra, and faces with sixteen MgMg8Ti4 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.05–3.16 Å. There are one shorter (3.34 Å) and one longer (3.37 Å) Mg–Ti bond lengths. In the fourth Mg site, Mg is bonded to nine Mg and three Ti atoms to form MgMg9Ti3 cuboctahedra that share corners with seven TiMg8Ti4 cuboctahedra, corners with eleven MgMg8Ti4 cuboctahedra, edges with five TiMg8Ti4 cuboctahedra, edges with thirteen MgMg8Ti4 cuboctahedra, faces with seven TiMg8Ti4 cuboctahedra, and faces with thirteen MgMg8Ti4 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.04–3.14 Å. There are two shorter (3.12 Å) and one longer (3.38 Å) Mg–Ti bond lengths. In the fifth Mg site, Mg is bonded to nine Mg and three Ti atoms to form distorted MgMg9Ti3 cuboctahedra that share corners with three TiMg8Ti4 cuboctahedra, corners with fifteen MgMg8Ti4 cuboctahedra, edges with six TiMg8Ti4 cuboctahedra, edges with twelve MgMg8Ti4 cuboctahedra, faces with seven TiMg8Ti4 cuboctahedra, and faces with thirteen MgMg8Ti4 cuboctahedra. Both Mg–Mg bond lengths are 3.09 Å. All Mg–Ti bond lengths are 3.06 Å. In the sixth Mg site, Mg is bonded to eight Mg and four Ti atoms to form distorted MgMg8Ti4 cuboctahedra that share corners with seven TiMg8Ti4 cuboctahedra, corners with eleven MgMg8Ti4 cuboctahedra, edges with eight TiMg8Ti4 cuboctahedra, edges with ten MgMg8Ti4 cuboctahedra, faces with six TiMg8Ti4 cuboctahedra, and faces with fourteen MgMg8Ti4 cuboctahedra. There are two shorter (3.04 Å) and one longer (3.10 Å) Mg–Mg bond lengths. There are a spread of Mg–Ti bond distances ranging from 3.08–3.37 Å. In the seventh Mg site, Mg is bonded to seven Mg and five Ti atoms to form MgMg7Ti5 cuboctahedra that share corners with seven TiMg8Ti4 cuboctahedra, corners with eleven MgMg8Ti4 cuboctahedra, edges with four TiMg8Ti4 cuboctahedra, edges with fourteen MgMg8Ti4 cuboctahedra, faces with nine TiMg8Ti4 cuboctahedra, and faces with eleven MgMg8Ti4 cuboctahedra. Both Mg–Mg bond lengths are 3.04 Å. There are a spread of Mg–Ti bond distances ranging from 3.10–3.21 Å. In the eighth Mg site, Mg is bonded to seven Mg and five Ti atoms to form MgMg7Ti5 cuboctahedra that share corners with seven TiMg8Ti4 cuboctahedra, corners with eleven MgMg8Ti4 cuboctahedra, edges with three equivalent TiMg8Ti4 cuboctahedra, edges with fifteen MgMg8Ti4 cuboctahedra, faces with nine TiMg8Ti4 cuboctahedra, and faces with eleven MgMg8Ti4 cuboctahedra. Both Mg–Mg bond lengths are 3.03 Å. There are a spread of Mg–Ti bond distances ranging from 3.09–3.19 Å. There are four inequivalent Ti sites. In the first Ti site, Ti is bonded to eight Mg and four Ti atoms to form TiMg8Ti4 cuboctahedra that share corners with six TiMg8Ti4 cuboctahedra, corners with twelve MgMg8Ti4 cuboctahedra, edges with seven TiMg8Ti4 cuboctahedra, edges with eleven MgMg8Ti4 cuboctahedra, faces with six TiMg8Ti4 cuboctahedra, and faces with fourteen MgMg8Ti4 cuboctahedra. There are a spread of Ti–Ti bond distances ranging from 2.61–2.88 Å. In the second Ti site, Ti is bonded to eight Mg and four Ti atoms to form TiMg8Ti4 cuboctahedra that share corners with four TiMg8Ti4 cuboctahedra, corners with fourteen MgMg8Ti4 cuboctahedra, edges with six TiMg8Ti4 cuboctahedra, edges with twelve MgMg8Ti4 cuboctahedra, faces with six TiMg8Ti4 cuboctahedra, and faces with fourteen MgMg8Ti4 cuboctahedra. There are one shorter (2.70 Å) and two longer (2.86 Å) Ti–Ti bond lengths. In the third Ti site, Ti is bonded to eight Mg and four Ti atoms to form TiMg8Ti4 cuboctahedra that share corners with seven TiMg8Ti4 cuboctahedra, corners with eleven MgMg8Ti4 cuboctahedra, edges with five TiMg8Ti4 cuboctahedra, edges with thirteen MgMg8Ti4 cuboctahedra, faces with six TiMg8Ti4 cuboctahedra, and faces with fourteen MgMg8Ti4 cuboctahedra. Both Ti–Ti bond lengths are 2.89 Å. In the fourth Ti site, Ti is bonded to six Mg and six Ti atoms to form TiMg6Ti6 cuboctahedra that share corners with three TiMg8Ti4 cuboctahedra, corners with fifteen MgMg8Ti4 cuboctahedra, edges with two TiMg8Ti4 cuboctahedra, edges with sixteen MgMg8Ti4 cuboctahedra, faces with eight TiMg8Ti4 cuboctahedra, and faces with twelve MgMg8Ti4 cuboctahedra.

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2020-05-02. Materials Data on Mg2Ti by Materials Project. https://doi.org/10.17188/1716485

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