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DOE OSTI · 1276904

Materials Data on Sr21(Mn2Sb9)2 by Materials Project

Abstract

Sr21(Mn2Sb9)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are twelve inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to six Sb+2.78- atoms to form distorted SrSb6 octahedra that share corners with seven SrSb6 octahedra, a cornercorner with one SrSb7 pentagonal bipyramid, corners with three MnSb4 tetrahedra, edges with three SrSb6 octahedra, an edgeedge with one MnSb4 tetrahedra, faces with two SrSb6 octahedra, and a faceface with one SrSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 35–51°. There are a spread of Sr–Sb bond distances ranging from 3.25–3.76 Å. In the second Sr2+ site, Sr2+ is bonded to six Sb+2.78- atoms to form SrSb6 octahedra that share corners with eight SrSb6 octahedra, a cornercorner with one SrSb7 pentagonal bipyramid, corners with three MnSb4 tetrahedra, edges with two equivalent SrSb6 octahedra, faces with three SrSb6 octahedra, and a faceface with one SrSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–61°. There are a spread of Sr–Sb bond distances ranging from 3.33–3.58 Å. In the third Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to five Sb+2.78- atoms. There are a spread of Sr–Sb bond distances ranging from 3.28–3.57 Å. In the fourth Sr2+ site, Sr2+ is bonded to six Sb+2.78- atoms to form distorted SrSb6 octahedra that share corners with eight SrSb6 octahedra, a cornercorner with one SrSb7 pentagonal bipyramid, corners with two MnSb4 tetrahedra, edges with two SrSb6 octahedra, an edgeedge with one MnSb4 tetrahedra, faces with three SrSb6 octahedra, a faceface with one SrSb7 pentagonal bipyramid, and a faceface with one MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–53°. There are a spread of Sr–Sb bond distances ranging from 3.31–3.62 Å. In the fifth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six Sb+2.78- atoms. There are a spread of Sr–Sb bond distances ranging from 3.23–3.89 Å. In the sixth Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven Sb+2.78- atoms. There are a spread of Sr–Sb bond distances ranging from 3.21–4.10 Å. In the seventh Sr2+ site, Sr2+ is bonded to six Sb+2.78- atoms to form distorted SrSb6 octahedra that share corners with seven SrSb6 octahedra, corners with two SrSb7 pentagonal bipyramids, a cornercorner with one MnSb4 tetrahedra, edges with three SrSb6 octahedra, an edgeedge with one MnSb4 tetrahedra, faces with four SrSb6 octahedra, and a faceface with one SrSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 33–50°. There are a spread of Sr–Sb bond distances ranging from 3.27–3.54 Å. In the eighth Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six Sb+2.78- atoms. There are a spread of Sr–Sb bond distances ranging from 3.27–3.89 Å. In the ninth Sr2+ site, Sr2+ is bonded to seven Sb+2.78- atoms to form SrSb7 pentagonal bipyramids that share corners with six SrSb6 octahedra, a cornercorner with one MnSb4 tetrahedra, an edgeedge with one SrSb7 pentagonal bipyramid, an edgeedge with one MnSb4 tetrahedra, faces with six SrSb6 octahedra, and faces with two equivalent MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–51°. There are a spread of Sr–Sb bond distances ranging from 3.40–3.83 Å. In the tenth Sr2+ site, Sr2+ is bonded to six Sb+2.78- atoms to form distorted SrSb6 octahedra that share corners with six SrSb6 octahedra, a cornercorner with one SrSb7 pentagonal bipyramid, corners with four MnSb4 tetrahedra, edges with three SrSb6 octahedra, an edgeedge with one MnSb4 tetrahedra, faces with two SrSb6 octahedra, and a faceface with one SrSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 37–74°. There are a spread of Sr–Sb bond distances ranging from 3.38–3.81 Å. In the eleventh Sr2+ site, Sr2+ is bonded to six Sb+2.78- atoms to form distorted SrSb6 octahedra that share corners with seven SrSb6 octahedra, a cornercorner with one SrSb7 pentagonal bipyramid, corners with two MnSb4 tetrahedra, edges with three SrSb6 octahedra, edges with two MnSb4 tetrahedra, faces with two SrSb6 octahedra, and a faceface with one SrSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 33–61°. There are a spread of Sr–Sb bond distances ranging from 3.23–3.54 Å. In the twelfth Sr2+ site, Sr2+ is bonded to seven Sb+2.78- atoms to form distorted SrSb7 pentagonal bipyramids that share corners with eight SrSb6 octahedra, corners with two MnSb4 tetrahedra, an edgeedge with one SrSb7 pentagonal bipyramid, faces with six SrSb6 octahedra, and faces with two equivalent MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–56°. There are a spread of Sr–Sb bond distances ranging from 3.44–3.78 Å. There are three inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to four Sb+2.78- atoms to form MnSb4 tetrahedra that share corners with eight SrSb6 octahedra, a cornercorner with one MnSb4 tetrahedra, edges with four SrSb6 octahedra, an edgeedge with one MnSb4 tetrahedra, and faces with two SrSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 36–58°. There are a spread of Mn–Sb bond distances ranging from 2.81–2.99 Å. In the second Mn2+ site, Mn2+ is bonded to four Sb+2.78- atoms to form MnSb4 tetrahedra that share corners with six SrSb6 octahedra, a cornercorner with one SrSb7 pentagonal bipyramid, corners with two equivalent MnSb4 tetrahedra, edges with two equivalent SrSb6 octahedra, an edgeedge with one SrSb7 pentagonal bipyramid, an edgeedge with one MnSb4 tetrahedra, and faces with two equivalent SrSb6 octahedra. The corner-sharing octahedra tilt angles range from 43–94°. There are a spread of Mn–Sb bond distances ranging from 2.77–2.84 Å. In the third Mn2+ site, Mn2+ is bonded to four Sb+2.78- atoms to form MnSb4 tetrahedra that share corners with eight SrSb6 octahedra, corners with two SrSb7 pentagonal bipyramids, edges with two equivalent SrSb6 octahedra, and an edgeedge with one MnSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–58°. There are a spread of Mn–Sb bond distances ranging from 2.81–2.85 Å. There are fourteen inequivalent Sb+2.78- sites. In the first Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Sr2+ atoms. In the second Sb+2.78- site, Sb+2.78- is bonded in a 7-coordinate geometry to six Sr2+ and one Mn2+ atom. In the third Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to six Sr2+ and two Mn2+ atoms. In the fourth Sb+2.78- site, Sb+2.78- is bonded in a 4-coordinate geometry to seven Sr2+ and two equivalent Mn2+ atoms. In the fifth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to seven Sr2+ and one Mn2+ atom. In the sixth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to six Sr2+ and three Mn2+ atoms. In the seventh Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Sr2+ and one Mn2+ atom. In the eighth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Sr2+ atoms. In the ninth Sb+2.78- site, Sb+2.78- is bonded in a 5-coordinate geometry to five Sr2+, one Mn2+, and one Sb+2.78- atom. The Sb–Sb bond length is 2.93 Å. In the tenth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to seven Sr2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.90 Å. In the eleventh Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Sr2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.97 Å. In the twelfth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Sr2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.99 Å. In the thirteenth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Sr2+ atoms. In the fourteenth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Sr2+ and one Mn2+ atom.

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2020-04-30. Materials Data on Sr21(Mn2Sb9)2 by Materials Project. https://doi.org/10.17188/1276904

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