Materials Data on Sr5Sb2As by Materials Project
Sr5Sb2As crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are four inequivalent Sr sites. In the first Sr site, Sr is bonded to four equivalent Sb and one As atom to form a mixture of distorted corner, edge, and face-sharing SrSb4As square pyramids. There are two shorter (3.42 Å) and two longer (3.45 Å) Sr–Sb bond lengths. The Sr–As bond length is 3.33 Å. In the second Sr site, Sr is bonded in a 5-coordinate geometry to four equivalent Sb and one As atom. There are two shorter (3.52 Å) and two longer (3.56 Å) Sr–Sb bond lengths. The Sr–As bond length is 3.11 Å. In the third Sr site, Sr is bonded in a 4-coordinate geometry to three equivalent Sb and two equivalent As atoms. There are a spread of Sr–Sb bond distances ranging from 3.54–3.93 Å. There are one shorter (3.12 Å) and one longer (3.32 Å) Sr–As bond lengths. In the fourth Sr site, Sr is bonded to four equivalent Sb and one As atom to form a mixture of distorted corner, edge, and face-sharing SrSb4As trigonal bipyramids. There are two shorter (3.46 Å) and two longer (3.53 Å) Sr–Sb bond lengths. The Sr–As bond length is 3.15 Å. Sb is bonded in a 9-coordinate geometry to nine Sr atoms. As is bonded to seven Sr atoms to form distorted edge-sharing AsSr7 pentagonal bipyramids.