DOI: 10.17188/1676468
title: Materials Data on Ba2Y2Co4O9 by Materials Project

description: Ba2Y2Co4O9 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.73–3.31 Å. In the second Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.77–3.34 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 a cornercorner with one YO7 pentagonal bipyramid, edges with three YO7 pentagonal bipyramids, and edges with four CoO5 trigonal bipyramids. There are a spread of Y–O bond distances ranging from 2.30–2.42 Å. In the second Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share a cornercorner with one YO7 pentagonal bipyramid, edges with three YO7 pentagonal bipyramids, and edges with four CoO5 trigonal bipyramids. There are a spread of Y–O bond distances ranging from 2.29–2.45 Å. There are four inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to five O2- atoms to form distorted CoO5 trigonal bipyramids that share corners with four CoO5 trigonal bipyramids and edges with four YO7 pentagonal bipyramids. There are a spread of Co–O bond distances ranging from 1.97–2.19 Å. In the second Co2+ site, Co2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Co–O bond distances ranging from 1.97–2.54 Å. In the third Co2+ site, Co2+ is bonded to five O2- atoms to form CoO5 trigonal bipyramids that share corners with four CoO5 trigonal bipyramids and edges with four YO7 pentagonal bipyramids. There are a spread of Co–O bond distances ranging from 2.02–2.13 Å. In the fourth Co2+ site, Co2+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Co–O bond distances ranging from 1.85–1.91 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to four Ba2+ and two Co2+ atoms to form a mixture of distorted edge and corner-sharing OBa4Co2 octahedra. The corner-sharing octahedra tilt angles range from 3–6°. In the second O2- site, O2- is bonded to four Ba2+ and two Co2+ atoms to form a mixture of distorted edge and corner-sharing OBa4Co2 octahedra. The corner-sharing octahedra tilt angles range from 3–6°. In the third O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two Co2+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two Co2+ atoms. In the fifth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two Co2+ atoms. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two Co2+ atoms. In the seventh O2- site, O2- is bonded in a distorted see-saw-like geometry to two Y3+ and two equivalent Co2+ atoms. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Ba2+, two Y3+, and two equivalent Co2+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Ba2+, two Y3+, and two equivalent Co2+ atoms.