Materials Data on BaY2CuO5 by Materials Project

Abstract

Y2BaCuO5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ba2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.64–3.31 Å. There are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with four equivalent YO7 pentagonal bipyramids, edges with three equivalent YO7 pentagonal bipyramids, edges with two equivalent CuO5 square pyramids, a faceface with one YO7 pentagonal bipyramid, and a faceface with one CuO5 square pyramid. There are a spread of Y–O bond distances ranging from 2.31–2.39 Å. In the second Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with five equivalent CuO5 square pyramids, edges with five YO7 pentagonal bipyramids, an edgeedge with one CuO5 square pyramid, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Y–O bond distances ranging from 2.29–2.40 Å. Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with five equivalent YO7 pentagonal bipyramids, edges with three YO7 pentagonal bipyramids, and a faceface with one YO7 pentagonal bipyramid. There are a spread of Cu–O bond distances ranging from 2.00–2.30 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Ba2+, two Y3+, and one Cu2+ atom to form a mixture of distorted edge and corner-sharing OBa3Y2Cu octahedra. The corner-sharing octahedral tilt angles are 5°. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, three Y3+, and one Cu2+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, three Y3+, and one Cu2+ atom.