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DOE OSTI · 1704209

Materials Data on Er7Co6Sn23 by Materials Project

Abstract

Er7Co6Sn23 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Er sites. In the first Er site, Er is bonded in a distorted hexagonal planar geometry to six Sn atoms. All Er–Sn bond lengths are 3.58 Å. In the second Er site, Er is bonded in a 12-coordinate geometry to two equivalent Co and ten Sn atoms. Both Er–Co bond lengths are 2.91 Å. There are a spread of Er–Sn bond distances ranging from 3.37–3.61 Å. In the third Er site, Er is bonded in a 12-coordinate geometry to two Co and ten Sn atoms. There are one shorter (2.90 Å) and one longer (2.92 Å) Er–Co bond lengths. There are a spread of Er–Sn bond distances ranging from 3.37–3.61 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded to two equivalent Er and four Sn atoms to form distorted CoEr2Sn4 octahedra that share a cornercorner with one SnSn6 octahedra, corners with two equivalent CoEr2Sn4 octahedra, and edges with two equivalent CoEr2Sn4 octahedra. The corner-sharing octahedra tilt angles range from 11–23°. There are a spread of Co–Sn bond distances ranging from 2.33–2.49 Å. In the second Co site, Co is bonded to two Er and four Sn atoms to form distorted CoEr2Sn4 octahedra that share a cornercorner with one SnSn6 octahedra, corners with two CoEr2Sn4 octahedra, and edges with two CoEr2Sn4 octahedra. The corner-sharing octahedra tilt angles range from 10–23°. There are a spread of Co–Sn bond distances ranging from 2.33–2.49 Å. There are nine inequivalent Sn sites. In the first Sn site, Sn is bonded in a distorted single-bond geometry to two equivalent Er, one Co, and two Sn atoms. There are one shorter (2.79 Å) and one longer (3.07 Å) Sn–Sn bond lengths. In the second Sn site, Sn is bonded in a distorted single-bond geometry to two Er, one Co, and two Sn atoms. There are one shorter (2.79 Å) and one longer (3.08 Å) Sn–Sn bond lengths. In the third Sn site, Sn is bonded to six Sn atoms to form SnSn6 octahedra that share corners with six CoEr2Sn4 octahedra. The corner-sharing octahedra tilt angles range from 10–11°. In the fourth Sn site, Sn is bonded in a 2-coordinate geometry to three Er and two Co atoms. In the fifth Sn site, Sn is bonded in a 2-coordinate geometry to three Er and two equivalent Co atoms. In the sixth Sn site, Sn is bonded in a distorted trigonal non-coplanar geometry to three Er, three Co, and one Sn atom. The Sn–Sn bond length is 3.01 Å. In the seventh Sn site, Sn is bonded in a 7-coordinate geometry to three Er and four Sn atoms. There are one shorter (3.15 Å) and two longer (3.16 Å) Sn–Sn bond lengths. In the eighth Sn site, Sn is bonded in a 8-coordinate geometry to four equivalent Er and four Sn atoms. Both Sn–Sn bond lengths are 3.20 Å. In the ninth Sn site, Sn is bonded in a 8-coordinate geometry to four Er and four Sn atoms. The Sn–Sn bond length is 3.20 Å.

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2020-05-03. Materials Data on Er7Co6Sn23 by Materials Project. https://doi.org/10.17188/1704209

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36 MATERIALS SCIENCE↗