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DOE OSTI · 1202878

Materials Data on Mn5As4 by Materials Project

Abstract

Mn5As4 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are five inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to five As+2.50- atoms to form MnAs5 square pyramids that share corners with six MnAs6 octahedra, corners with four equivalent MnAs5 square pyramids, corners with two equivalent MnAs5 trigonal bipyramids, edges with two equivalent MnAs6 octahedra, edges with three MnAs5 square pyramids, edges with two equivalent MnAs5 trigonal bipyramids, and a faceface with one MnAs6 octahedra. The corner-sharing octahedra tilt angles range from 46–67°. There are a spread of Mn–As bond distances ranging from 2.44–2.49 Å. In the second Mn2+ site, Mn2+ is bonded to six As+2.50- atoms to form MnAs6 octahedra that share corners with six equivalent MnAs6 octahedra, corners with six MnAs5 square pyramids, corners with three equivalent MnAs5 trigonal bipyramids, edges with two equivalent MnAs6 octahedra, edges with three equivalent MnAs5 square pyramids, edges with two equivalent MnAs5 trigonal bipyramids, a faceface with one MnAs6 octahedra, and a faceface with one MnAs5 square pyramid. The corner-sharing octahedra tilt angles range from 50–54°. There are a spread of Mn–As bond distances ranging from 2.43–2.66 Å. In the third Mn2+ site, Mn2+ is bonded to six As+2.50- atoms to form MnAs6 octahedra that share corners with six equivalent MnAs6 octahedra, corners with six MnAs5 square pyramids, corners with five equivalent MnAs5 trigonal bipyramids, edges with two equivalent MnAs6 octahedra, edges with two equivalent MnAs5 square pyramids, a faceface with one MnAs6 octahedra, a faceface with one MnAs5 square pyramid, and a faceface with one MnAs5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 50–54°. There are a spread of Mn–As bond distances ranging from 2.51–2.58 Å. In the fourth Mn2+ site, Mn2+ is bonded to five As+2.50- atoms to form MnAs5 trigonal bipyramids that share corners with eight MnAs6 octahedra, corners with three MnAs5 square pyramids, corners with two equivalent MnAs5 trigonal bipyramids, edges with two equivalent MnAs6 octahedra, edges with four MnAs5 square pyramids, and a faceface with one MnAs6 octahedra. The corner-sharing octahedra tilt angles range from 38–51°. There are a spread of Mn–As bond distances ranging from 2.42–2.54 Å. In the fifth Mn2+ site, Mn2+ is bonded to five As+2.50- atoms to form MnAs5 square pyramids that share corners with six MnAs6 octahedra, corners with four equivalent MnAs5 square pyramids, a cornercorner with one MnAs5 trigonal bipyramid, edges with three equivalent MnAs6 octahedra, edges with three MnAs5 square pyramids, edges with two equivalent MnAs5 trigonal bipyramids, and a faceface with one MnAs6 octahedra. The corner-sharing octahedra tilt angles range from 20–58°. There are a spread of Mn–As bond distances ranging from 2.41–2.54 Å. There are four inequivalent As+2.50- sites. In the first As+2.50- site, As+2.50- is bonded in a 6-coordinate geometry to six Mn2+ atoms. In the second As+2.50- site, As+2.50- is bonded to seven Mn2+ atoms to form distorted face-sharing AsMn7 pentagonal bipyramids. In the third As+2.50- site, As+2.50- is bonded in a 7-coordinate geometry to seven Mn2+ atoms. In the fourth As+2.50- site, As+2.50- is bonded in a 7-coordinate geometry to seven Mn2+ atoms.

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2020-07-15. Materials Data on Mn5As4 by Materials Project. https://doi.org/10.17188/1202878

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