Materials Data on MgTi by Materials Project

Abstract

MgTi crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded to six Mg and six Ti atoms to form distorted MgMg6Ti6 cuboctahedra that share corners with six equivalent MgMg6Ti6 cuboctahedra, corners with six equivalent TiMg4Ti8 cuboctahedra, edges with fifteen TiMg4Ti8 cuboctahedra, faces with eight TiMg4Ti8 cuboctahedra, and faces with ten MgMg6Ti6 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.96–3.33 Å. There are two shorter (3.01 Å) and four longer (3.07 Å) Mg–Ti bond lengths. In the second Mg site, Mg is bonded in a 12-coordinate geometry to eight Mg and four Ti atoms. There are two shorter (2.96 Å) and four longer (3.07 Å) Mg–Mg bond lengths. There are two shorter (2.97 Å) and two longer (3.05 Å) Mg–Ti bond lengths. In the third Mg site, Mg is bonded to eight Mg and four Ti atoms to form MgMg8Ti4 cuboctahedra that share corners with six equivalent MgMg8Ti4 cuboctahedra, corners with twelve TiMg4Ti8 cuboctahedra, edges with fourteen TiMg4Ti8 cuboctahedra, faces with six TiMg4Ti8 cuboctahedra, and faces with ten MgMg6Ti6 cuboctahedra. Both Mg–Mg bond lengths are 2.96 Å. There are two shorter (3.30 Å) and two longer (3.33 Å) Mg–Ti bond lengths. There are three inequivalent Ti sites. In the first Ti site, Ti is bonded to four Mg and eight Ti atoms to form TiMg4Ti8 cuboctahedra that share corners with six equivalent MgMg6Ti6 cuboctahedra, corners with six equivalent TiMg4Ti8 cuboctahedra, edges with four equivalent TiMg4Ti8 cuboctahedra, edges with eleven MgMg6Ti6 cuboctahedra, faces with four MgMg6Ti6 cuboctahedra, and faces with fourteen TiMg4Ti8 cuboctahedra. There are a spread of Ti–Ti bond distances ranging from 2.79–2.97 Å. In the second Ti site, Ti is bonded to six Mg and six Ti atoms to form TiMg6Ti6 cuboctahedra that share corners with six equivalent MgMg8Ti4 cuboctahedra, corners with twelve TiMg4Ti8 cuboctahedra, edges with three equivalent TiMg4Ti8 cuboctahedra, edges with seven MgMg8Ti4 cuboctahedra, faces with six MgMg6Ti6 cuboctahedra, and faces with twelve TiMg4Ti8 cuboctahedra. There are two shorter (2.76 Å) and two longer (2.96 Å) Ti–Ti bond lengths. In the third Ti site, Ti is bonded to four Mg and eight Ti atoms to form distorted TiMg4Ti8 cuboctahedra that share corners with six equivalent MgMg8Ti4 cuboctahedra, corners with twelve TiMg4Ti8 cuboctahedra, edges with seven TiMg4Ti8 cuboctahedra, edges with eleven MgMg6Ti6 cuboctahedra, faces with four MgMg6Ti6 cuboctahedra, and faces with ten TiMg4Ti8 cuboctahedra. Both Ti–Ti bond lengths are 2.96 Å.