Materials Data on Sr2Cu(OF)2 by Materials Project

Abstract

Sr2Cu(OF)2 crystallizes in the orthorhombic Imm2 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 four O2- and four F1- atoms. There are two shorter (2.36 Å) and two longer (2.91 Å) Sr–O bond lengths. There are two shorter (2.46 Å) and two longer (2.84 Å) Sr–F bond lengths. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to four O2- and four F1- atoms. There are two shorter (2.48 Å) and two longer (2.95 Å) Sr–O bond lengths. There are two shorter (2.39 Å) and two longer (2.61 Å) Sr–F bond lengths. Cu2+ is bonded in a rectangular see-saw-like geometry to two equivalent O2- and two equivalent F1- atoms. Both Cu–O bond lengths are 1.92 Å. Both Cu–F bond lengths are 2.21 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four Sr2+ atoms to form OSr4 tetrahedra that share corners with six equivalent FSr4Cu2 octahedra, corners with four equivalent OSr4 tetrahedra, an edgeedge with one FSr4Cu2 octahedra, and edges with four equivalent FSr4 tetrahedra. The corner-sharing octahedra tilt angles range from 12–72°. In the second O2- site, O2- is bonded in a distorted linear geometry to four Sr2+ and two equivalent Cu2+ atoms. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to four Sr2+ atoms to form distorted FSr4 tetrahedra that share corners with six equivalent FSr4Cu2 octahedra, corners with four equivalent FSr4 tetrahedra, an edgeedge with one FSr4Cu2 octahedra, and edges with four equivalent OSr4 tetrahedra. The corner-sharing octahedra tilt angles range from 6–71°. In the second F1- site, F1- is bonded to four Sr2+ and two equivalent Cu2+ atoms to form distorted FSr4Cu2 octahedra that share corners with two equivalent FSr4Cu2 octahedra, corners with six equivalent OSr4 tetrahedra, corners with six equivalent FSr4 tetrahedra, edges with two equivalent FSr4Cu2 octahedra, an edgeedge with one OSr4 tetrahedra, and an edgeedge with one FSr4 tetrahedra. The corner-sharing octahedral tilt angles are 7°.