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DOE OSTI · 1749537

Materials Data on MgTi2 by Materials Project

Abstract

MgTi2 is beta-derived structured and crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to four Mg and eight Ti atoms to form distorted MgMg4Ti8 cuboctahedra that share corners with six MgMg4Ti8 cuboctahedra, corners with twelve TiMg4Ti8 cuboctahedra, edges with seven MgMg4Ti8 cuboctahedra, edges with eleven TiMg4Ti8 cuboctahedra, faces with six MgMg4Ti8 cuboctahedra, and faces with fourteen TiMg4Ti8 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.97–3.14 Å. There are a spread of Mg–Ti bond distances ranging from 2.92–3.07 Å. In the second Mg site, Mg is bonded to four Mg and eight Ti atoms to form distorted MgMg4Ti8 cuboctahedra that share corners with four MgMg4Ti8 cuboctahedra, corners with fourteen TiMg4Ti8 cuboctahedra, edges with six MgMg4Ti8 cuboctahedra, edges with twelve TiMg4Ti8 cuboctahedra, faces with six MgMg4Ti8 cuboctahedra, and faces with fourteen TiMg4Ti8 cuboctahedra. There are two shorter (2.97 Å) and one longer (3.14 Å) Mg–Mg bond lengths. There are a spread of Mg–Ti bond distances ranging from 2.93–3.06 Å. In the third Mg site, Mg is bonded to four Mg and eight Ti atoms to form distorted MgMg4Ti8 cuboctahedra that share corners with seven MgMg4Ti8 cuboctahedra, corners with eleven TiMg4Ti8 cuboctahedra, edges with five MgMg4Ti8 cuboctahedra, edges with thirteen TiMg4Ti8 cuboctahedra, faces with six MgMg4Ti8 cuboctahedra, and faces with fourteen TiMg4Ti8 cuboctahedra. Both Mg–Mg bond lengths are 2.96 Å. There are a spread of Mg–Ti bond distances ranging from 2.90–3.00 Å. In the fourth Mg site, Mg is bonded to six Mg and six Ti atoms to form MgMg6Ti6 cuboctahedra that share corners with three MgMg4Ti8 cuboctahedra, corners with fifteen TiMg4Ti8 cuboctahedra, edges with two MgMg4Ti8 cuboctahedra, edges with sixteen TiMg4Ti8 cuboctahedra, faces with eight MgMg4Ti8 cuboctahedra, and faces with twelve TiMg4Ti8 cuboctahedra. There are a spread of Mg–Ti bond distances ranging from 3.06–3.14 Å. There are eight inequivalent Ti sites. In the first Ti site, Ti is bonded to four Mg and eight Ti atoms to form distorted TiMg4Ti8 cuboctahedra that share corners with eight MgMg4Ti8 cuboctahedra, corners with ten TiMg4Ti8 cuboctahedra, edges with seven MgMg4Ti8 cuboctahedra, edges with eleven TiMg4Ti8 cuboctahedra, faces with six MgMg4Ti8 cuboctahedra, and faces with fourteen TiMg4Ti8 cuboctahedra. There are a spread of Ti–Ti bond distances ranging from 2.84–3.12 Å. In the second Ti site, Ti is bonded to four Mg and eight Ti atoms to form distorted TiMg4Ti8 cuboctahedra that share corners with six MgMg4Ti8 cuboctahedra, corners with twelve TiMg4Ti8 cuboctahedra, edges with eight TiMg4Ti8 cuboctahedra, edges with ten MgMg4Ti8 cuboctahedra, faces with six MgMg4Ti8 cuboctahedra, and faces with fourteen TiMg4Ti8 cuboctahedra. There are a spread of Ti–Ti bond distances ranging from 2.81–3.16 Å. In the third Ti site, Ti is bonded to two Mg and ten Ti atoms to form distorted TiMg2Ti10 cuboctahedra that share corners with seven MgMg4Ti8 cuboctahedra, corners with eleven TiMg4Ti8 cuboctahedra, edges with nine MgMg4Ti8 cuboctahedra, edges with nine TiMg4Ti8 cuboctahedra, faces with four MgMg4Ti8 cuboctahedra, and faces with sixteen TiMg4Ti8 cuboctahedra. There are a spread of Ti–Ti bond distances ranging from 2.87–3.08 Å. In the fourth Ti site, Ti is bonded to three Mg and nine Ti atoms to form distorted TiMg3Ti9 cuboctahedra that share corners with seven MgMg4Ti8 cuboctahedra, corners with eleven TiMg4Ti8 cuboctahedra, edges with five MgMg4Ti8 cuboctahedra, edges with thirteen TiMg4Ti8 cuboctahedra, faces with seven MgMg4Ti8 cuboctahedra, and faces with thirteen TiMg4Ti8 cuboctahedra. There are a spread of Ti–Ti bond distances ranging from 2.92–3.04 Å. In the fifth Ti site, Ti is bonded to three Mg and nine Ti atoms to form distorted TiMg3Ti9 cuboctahedra that share corners with three MgMg4Ti8 cuboctahedra, corners with fifteen TiMg4Ti8 cuboctahedra, edges with six MgMg4Ti8 cuboctahedra, edges with twelve TiMg4Ti8 cuboctahedra, faces with seven MgMg4Ti8 cuboctahedra, and faces with thirteen TiMg4Ti8 cuboctahedra. There are one shorter (3.06 Å) and one longer (3.12 Å) Ti–Ti bond lengths. In the sixth Ti site, Ti is bonded to four Mg and eight Ti atoms to form distorted TiMg4Ti8 cuboctahedra that share corners with seven MgMg4Ti8 cuboctahedra, corners with eleven TiMg4Ti8 cuboctahedra, edges with eight MgMg4Ti8 cuboctahedra, edges with ten TiMg4Ti8 cuboctahedra, faces with six MgMg4Ti8 cuboctahedra, and faces with fourteen TiMg4Ti8 cuboctahedra. There are two shorter (2.90 Å) and one longer (3.08 Å) Ti–Ti bond lengths. In the seventh Ti site, Ti is bonded to five Mg and seven Ti atoms to form distorted TiMg5Ti7 cuboctahedra that share corners with seven MgMg4Ti8 cuboctahedra, corners with eleven TiMg4Ti8 cuboctahedra, edges with four MgMg4Ti8 cuboctahedra, edges with fourteen TiMg4Ti8 cuboctahedra, faces with nine MgMg4Ti8 cuboctahedra, and faces with eleven TiMg4Ti8 cuboctahedra. Both Ti–Ti bond lengths are 2.95 Å. In the eighth Ti site, Ti is bonded to five Mg and seven Ti atoms to form distorted TiMg5Ti7 cuboctahedra that share corners with seven MgMg4Ti8 cuboctahedra, corners with eleven TiMg4Ti8 cuboctahedra, edges with three equivalent MgMg4Ti8 cuboctahedra, edges with fifteen TiMg4Ti8 cuboctahedra, faces with nine MgMg4Ti8 cuboctahedra, and faces with eleven TiMg4Ti8 cuboctahedra. Both Ti–Ti bond lengths are 2.91 Å.

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2020-05-03. Materials Data on MgTi2 by Materials Project. https://doi.org/10.17188/1749537

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