Materials Data on BaSrNdCu3O7 by Materials Project
BaSrNdCu3O7 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 2.75–3.03 Å. Sr2+ is bonded in a distorted q6 geometry to ten O2- atoms. There are a spread of Sr–O bond distances ranging from 2.75–2.95 Å. Nd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Nd–O bond distances ranging from 2.45–2.48 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 1.94–2.24 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 1.94–2.10 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 to four equivalent Ba2+ and two Cu+2.33+ atoms to form distorted OBa4Cu2 octahedra that share corners with nine OBa4Cu2 octahedra, edges with four equivalent OBa4Cu2 octahedra, and faces with two equivalent OBa2Sr2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–67°. In the second O2- site, O2- is bonded to four equivalent Sr2+ and two Cu+2.33+ atoms to form distorted OSr4Cu2 octahedra that share corners with nine OBa4Cu2 octahedra, edges with four equivalent OSr4Cu2 octahedra, and faces with two equivalent OBa2Sr2Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–65°. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Nd3+, and two equivalent Cu+2.33+ atoms. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Nd3+, and two equivalent Cu+2.33+ atoms. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Sr2+, two equivalent Nd3+, and two equivalent Cu+2.33+ atoms. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Sr2+, two equivalent Nd3+, and two equivalent Cu+2.33+ atoms. In the seventh O2- site, O2- is bonded to two equivalent Ba2+, two equivalent Sr2+, and two equivalent Cu+2.33+ atoms to form distorted OBa2Sr2Cu2 octahedra that share corners with ten OBa4Cu2 octahedra, edges with two equivalent OBa2Sr2Cu2 octahedra, and faces with four OBa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 5–67°.