DOI: 10.17188/1663450
title: Materials Data on Sr3(SnAs2)2 by Materials Project

description: Sr3Sn2As4 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are seven inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to six As3- atoms to form a mixture of corner and edge-sharing SrAs6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are a spread of Sr–As bond distances ranging from 3.09–3.25 Å. In the second Sr2+ site, Sr2+ is bonded to six As3- atoms to form a mixture of corner and edge-sharing SrAs6 octahedra. The corner-sharing octahedra tilt angles range from 4–9°. There are four shorter (3.25 Å) and two longer (3.29 Å) Sr–As bond lengths. In the third Sr2+ site, Sr2+ is bonded to six As3- atoms to form a mixture of distorted corner and edge-sharing SrAs6 octahedra. The corner-sharing octahedra tilt angles range from 9–11°. There are two shorter (3.24 Å) and four longer (3.31 Å) Sr–As bond lengths. In the fourth Sr2+ site, Sr2+ is bonded to six As3- atoms to form a mixture of corner and edge-sharing SrAs6 octahedra. The corner-sharing octahedra tilt angles range from 4–11°. There are a spread of Sr–As bond distances ranging from 3.15–3.42 Å. In the fifth Sr2+ site, Sr2+ is bonded to six As3- atoms to form a mixture of corner and edge-sharing SrAs6 octahedra. The corner-sharing octahedra tilt angles range from 2–5°. There are a spread of Sr–As bond distances ranging from 3.18–3.36 Å. In the sixth Sr2+ site, Sr2+ is bonded to six As3- atoms to form a mixture of corner and edge-sharing SrAs6 octahedra. The corner-sharing octahedra tilt angles range from 1–4°. There are a spread of Sr–As bond distances ranging from 3.16–3.34 Å. In the seventh Sr2+ site, Sr2+ is bonded to six As3- atoms to form a mixture of corner and edge-sharing SrAs6 octahedra. The corner-sharing octahedra tilt angles range from 4–7°. There are two shorter (3.20 Å) and four longer (3.24 Å) Sr–As bond lengths. There are three inequivalent Sn3+ sites. In the first Sn3+ site, Sn3+ is bonded in a trigonal non-coplanar geometry to three As3- atoms. There are a spread of Sn–As bond distances ranging from 2.62–2.70 Å. In the second Sn3+ site, Sn3+ is bonded in a trigonal non-coplanar geometry to three As3- atoms. There are a spread of Sn–As bond distances ranging from 2.59–2.70 Å. In the third Sn3+ site, Sn3+ is bonded in a trigonal non-coplanar geometry to three As3- atoms. There are a spread of Sn–As bond distances ranging from 2.61–2.70 Å. There are seven inequivalent As3- sites. In the first As3- site, As3- is bonded to five Sr2+ and one Sn3+ atom to form a mixture of corner and edge-sharing AsSr5Sn octahedra. The corner-sharing octahedra tilt angles range from 0–83°. In the second As3- site, As3- is bonded to four Sr2+ and two equivalent Sn3+ atoms to form a mixture of distorted corner and edge-sharing AsSr4Sn2 octahedra. The corner-sharing octahedra tilt angles range from 0–77°. In the third As3- site, As3- is bonded to four Sr2+ and two equivalent Sn3+ atoms to form AsSr4Sn2 octahedra that share corners with six AsSr4Sn2 octahedra and edges with nine AsSr5Sn octahedra. The corner-sharing octahedra tilt angles range from 3–76°. In the fourth As3- site, As3- is bonded to five Sr2+ and one Sn3+ atom to form AsSr5Sn octahedra that share corners with seven AsSr4Sn2 octahedra and edges with ten AsSr5Sn octahedra. The corner-sharing octahedra tilt angles range from 6–83°. In the fifth As3- site, As3- is bonded to four Sr2+ and two Sn3+ atoms to form distorted AsSr4Sn2 octahedra that share corners with six AsSr5Sn octahedra and edges with nine AsSr4Sn2 octahedra. The corner-sharing octahedra tilt angles range from 0–77°. In the sixth As3- site, As3- is bonded to four Sr2+ and two Sn3+ atoms to form AsSr4Sn2 octahedra that share corners with six AsSr4Sn2 octahedra and edges with nine AsSr5Sn octahedra. The corner-sharing octahedra tilt angles range from 3–80°. In the seventh As3- site, As3- is bonded to five Sr2+ and one Sn3+ atom to form AsSr5Sn octahedra that share corners with seven AsSr4Sn2 octahedra and edges with ten AsSr5Sn octahedra. The corner-sharing octahedra tilt angles range from 3–80°.