Materials Data on Sr2SmGaCu2O7 by Materials Project

Abstract

Sr2SmCu2GaO7 crystallizes in the orthorhombic Ima2 space group. The structure is three-dimensional. Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.48–3.22 Å. Sm3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Sm–O bond distances ranging from 2.44–2.49 Å. Cu2+ 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 1.95–2.42 Å. Ga3+ is bonded to four O2- atoms to form GaO4 tetrahedra that share corners with two equivalent CuO5 square pyramids and corners with two equivalent GaO4 tetrahedra. There is two shorter (1.85 Å) and two longer (1.92 Å) Ga–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Sr2+, one Cu2+, and one Ga3+ atom. In the second O2- site, O2- is bonded to two equivalent Sr2+ and two equivalent Ga3+ atoms to form distorted corner-sharing OSr2Ga2 tetrahedra. In the third O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Sr2+, two equivalent Sm3+, and two equivalent Cu2+ atoms. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Sr2+, two equivalent Sm3+, and two equivalent Cu2+ atoms.