Materials Data on Sr4CaYGa2(Cu2O7)2 by Materials Project

Abstract

Sr4CaYGa2(Cu2O7)2 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.48–3.13 Å. In the second Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.48–3.12 Å. Ca2+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.44–2.51 Å. Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.39 Å) and four longer (2.44 Å) Y–O bond lengths. There are two inequivalent Cu+2.25+ sites. In the first Cu+2.25+ site, Cu+2.25+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with four equivalent CuO5 square pyramids and a cornercorner with one GaO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.41 Å. In the second Cu+2.25+ site, Cu+2.25+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with four equivalent CuO5 square pyramids and a cornercorner with one GaO4 tetrahedra. There are a spread of Cu–O bond distances ranging from 1.93–2.40 Å. Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with two CuO5 square pyramids and corners with two equivalent GaO4 tetrahedra. There are a spread of Ga–O bond distances ranging from 1.85–1.92 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four Sr2+, one Cu+2.25+, and one Ga3+ atom. In the second O2- site, O2- is bonded to two Sr2+, one Ca2+, one Y3+, and two Cu+2.25+ atoms to form distorted OSr2CaYCu2 octahedra that share corners with two equivalent OSr2CaYCu2 octahedra and corners with two equivalent OSr2Ga2 tetrahedra. The corner-sharing octahedra tilt angles range from 65–67°. In the third O2- site, O2- is bonded in a 6-coordinate geometry to two Sr2+, one Ca2+, one Y3+, and two Cu+2.25+ atoms. In the fourth O2- site, O2- is bonded to two Sr2+ and two equivalent Ga3+ atoms to form distorted OSr2Ga2 tetrahedra that share corners with two equivalent OSr2CaYCu2 octahedra and corners with two equivalent OSr2Ga2 tetrahedra. The corner-sharing octahedra tilt angles range from 53–66°. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to two Sr2+, one Ca2+, one Y3+, and two Cu+2.25+ atoms. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to two Sr2+, one Ca2+, one Y3+, and two Cu+2.25+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to four Sr2+, one Cu+2.25+, and one Ga3+ atom.