Materials Data on Sr5(Br4Cl)2 by Materials Project
Sr5(Br4Cl)2 crystallizes in the tetragonal P4/n space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to eight Br1- atoms. There are four shorter (3.16 Å) and four longer (3.18 Å) Sr–Br bond lengths. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to six Br1- and two Cl1- atoms. There are a spread of Sr–Br bond distances ranging from 3.12–3.52 Å. There are one shorter (3.02 Å) and one longer (3.04 Å) Sr–Cl bond lengths. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded to four Sr2+ atoms to form distorted BrSr4 trigonal pyramids that share corners with four ClSr4 tetrahedra, corners with three equivalent BrSr4 trigonal pyramids, an edgeedge with one ClSr4 tetrahedra, and edges with three equivalent BrSr4 trigonal pyramids. In the second Br1- site, Br1- is bonded in a 4-coordinate geometry to four Sr2+ atoms. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded to four equivalent Sr2+ atoms to form ClSr4 tetrahedra that share corners with twelve equivalent BrSr4 trigonal pyramids and edges with two equivalent ClSr4 tetrahedra. In the second Cl1- site, Cl1- is bonded to four equivalent Sr2+ atoms to form ClSr4 tetrahedra that share corners with four equivalent BrSr4 trigonal pyramids, edges with two equivalent ClSr4 tetrahedra, and edges with four equivalent BrSr4 trigonal pyramids.