DOE OSTI2020
Sr5Sb3 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 Sb atoms to form distorted SrSb4 trigonal pyramids that share corners with six SrSb5 square pyramids, corners with six equivalent SrSb4 trigonal pyramids, edges with three SrSb5 square pyramids, and an edgeedge with one SrSb4 trigonal pyramid. There are a spread of Sr–Sb bond distances ranging from 3.22–3.51 Å. In the second Sr site, Sr is bonded to five Sb atoms to form distorted SrSb5 square pyramids that share corners with eight SrSb5 square pyramids, corners with four equivalent SrSb4 trigonal pyramids, an edgeedge with one SrSb5 square pyramid, edges with four equivalent SrSb4 trigonal pyramids, and a faceface with one SrSb5 square pyramid. There are a spread of Sr–Sb bond distances ranging from 3.35–3.57 Å. In the third Sr site, Sr is bonded in a 5-coordinate geometry to five Sb atoms. There are a spread of Sr–Sb bond distances ranging from 3.27–3.65 Å. In the fourth Sr site, Sr is bonded to five Sb atoms to form distorted SrSb5 square pyramids that share corners with four equivalent SrSb5 square pyramids, corners with eight equivalent SrSb4 trigonal pyramids, edges with three SrSb5 square pyramids, edges with two equivalent SrSb4 trigonal pyramids, and a faceface with one SrSb5 square pyramid. There are a spread of Sr–Sb bond distances ranging from 3.43–3.49 Å. There are two inequivalent Sb sites. In the first Sb site, Sb is bonded in a 8-coordinate geometry to eight Sr atoms. In the second Sb site, Sb is bonded to seven Sr atoms to form distorted edge-sharing SbSr7 pentagonal bipyramids.