Materials Data on Ba2CuO4 by Materials Project
Ba2CuO4 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ba is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ba–O bond distances ranging from 2.75–2.98 Å. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded in a square co-planar geometry to four equivalent O atoms. All Cu–O bond lengths are 1.95 Å. In the second Cu site, Cu is bonded in a square co-planar geometry to four equivalent O atoms. All Cu–O bond lengths are 1.94 Å. There are three inequivalent O sites. In the first O site, O is bonded in a 5-coordinate geometry to four equivalent Ba and one O atom. The O–O bond length is 1.54 Å. In the second O site, O is bonded in a 5-coordinate geometry to four equivalent Ba and one O atom. In the third O site, O is bonded to four equivalent Ba and two Cu atoms to form a mixture of distorted face, edge, and corner-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 0°.