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DOE OSTI · 1693290

Materials Data on Mg5MnSb4 by Materials Project

Abstract

Mg5MnSb4 crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. there are five inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six Sb3- atoms to form MgSb6 octahedra that share corners with three equivalent MnSb4 tetrahedra, corners with nine MgSb4 tetrahedra, edges with six equivalent MgSb6 octahedra, and edges with six MgSb4 tetrahedra. There are three shorter (3.10 Å) and three longer (3.12 Å) Mg–Sb bond lengths. In the second Mg2+ site, Mg2+ is bonded to six Sb3- atoms to form MgSb6 octahedra that share corners with three equivalent MnSb4 tetrahedra, corners with nine MgSb4 tetrahedra, edges with six equivalent MgSb6 octahedra, edges with three equivalent MgSb4 tetrahedra, and edges with three equivalent MnSb4 tetrahedra. There are three shorter (3.10 Å) and three longer (3.12 Å) Mg–Sb bond lengths. In the third Mg2+ site, Mg2+ is bonded to four Sb3- atoms to form MgSb4 tetrahedra that share corners with six MgSb6 octahedra, corners with six equivalent MgSb4 tetrahedra, edges with three equivalent MgSb6 octahedra, and edges with three equivalent MgSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 10–58°. There are three shorter (2.84 Å) and one longer (2.95 Å) Mg–Sb bond lengths. In the fourth Mg2+ site, Mg2+ is bonded to four Sb3- atoms to form MgSb4 tetrahedra that share corners with six MgSb6 octahedra, corners with six equivalent MgSb4 tetrahedra, edges with three equivalent MgSb6 octahedra, and edges with three equivalent MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 11–58°. There are three shorter (2.83 Å) and one longer (2.87 Å) Mg–Sb bond lengths. In the fifth Mg2+ site, Mg2+ is bonded to four Sb3- atoms to form MgSb4 tetrahedra that share corners with six MgSb6 octahedra, corners with six equivalent MgSb4 tetrahedra, edges with three equivalent MgSb6 octahedra, and edges with three equivalent MgSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 10–58°. There are three shorter (2.84 Å) and one longer (2.95 Å) Mg–Sb bond lengths. Mn2+ is bonded to four Sb3- atoms to form MnSb4 tetrahedra that share corners with six MgSb6 octahedra, corners with six equivalent MnSb4 tetrahedra, edges with three equivalent MgSb6 octahedra, and edges with three equivalent MgSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 11–58°. There are three shorter (2.83 Å) and one longer (2.88 Å) Mn–Sb bond lengths. There are four inequivalent Sb3- sites. In the first Sb3- site, Sb3- is bonded to six Mg2+ and one Mn2+ atom to form distorted SbMg6Mn pentagonal bipyramids that share corners with three equivalent SbMg7 pentagonal bipyramids and edges with twelve SbMg4Mn3 pentagonal bipyramids. In the second Sb3- site, Sb3- is bonded to seven Mg2+ atoms to form a mixture of distorted corner and edge-sharing SbMg7 pentagonal bipyramids. In the third Sb3- site, Sb3- is bonded to four Mg2+ and three equivalent Mn2+ atoms to form distorted SbMg4Mn3 pentagonal bipyramids that share corners with three equivalent SbMg7 pentagonal bipyramids and edges with twelve SbMg4Mn3 pentagonal bipyramids. In the fourth Sb3- site, Sb3- is bonded to seven Mg2+ atoms to form distorted SbMg7 pentagonal bipyramids that share corners with three equivalent SbMg6Mn pentagonal bipyramids and edges with twelve SbMg7 pentagonal bipyramids.

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2020-05-03. Materials Data on Mg5MnSb4 by Materials Project. https://doi.org/10.17188/1693290

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36 MATERIALS SCIENCE↗