Materials Data on BaSrSmCu3O7 by Materials Project
BaSrSmCu3O7 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.74–3.07 Å. Sr2+ is bonded in a distorted q6 geometry to ten O2- atoms. There are a spread of Sr–O bond distances ranging from 2.72–2.98 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 2.43–2.46 Å. There are three inequivalent Cu+2.33+ sites. In the first Cu+2.33+ site, Cu+2.33+ is bonded to five O2- atoms to form corner-sharing CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.93–2.28 Å. In the second Cu+2.33+ site, Cu+2.33+ is bonded to five O2- atoms to form corner-sharing CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.93–2.10 Å. In the third Cu+2.33+ site, Cu+2.33+ is bonded in a square co-planar geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.86–1.97 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Sm3+, and two equivalent Cu+2.33+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Sm3+, and two equivalent Cu+2.33+ atoms. In the third O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Sr2+, two equivalent Sm3+, and two equivalent Cu+2.33+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sr2+, two equivalent Sm3+, and two equivalent Cu+2.33+ atoms. In the fifth O2- site, O2- is bonded to four equivalent Ba2+ and two Cu+2.33+ atoms to form a mixture of distorted corner and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–11°. In the sixth O2- site, O2- is bonded to four equivalent Sr2+ and two Cu+2.33+ atoms to form distorted OSr4Cu2 octahedra that share corners with five OBa4Cu2 octahedra and edges with four equivalent OSr4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the seventh O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Sr2+, and two equivalent Cu+2.33+ atoms.