Materials Data on BaAl2C2O11 by Materials Project
(BaAl2(CO5)2)2O2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional and consists of four water molecules and one BaAl2(CO5)2 framework. In the BaAl2(CO5)2 framework, Ba is bonded in a 5-coordinate geometry to nine O atoms. There are a spread of Ba–O bond distances ranging from 2.62–3.16 Å. Al is bonded to six O atoms to form distorted edge-sharing AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.81–1.96 Å. There are two inequivalent C sites. In the first C site, C is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.28 Å) and two longer (1.31 Å) C–O bond length. In the second C site, C is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.27 Å) and two longer (1.30 Å) C–O bond length. There are eight inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to one Ba, one Al, and one C atom. In the second O site, O is bonded in a distorted single-bond geometry to one Ba and one C atom. In the third O site, O is bonded in a distorted trigonal non-coplanar geometry to one Ba and two equivalent Al atoms. In the fourth O site, O is bonded in a 2-coordinate geometry to two equivalent Al and one O atom. The O–O bond length is 1.51 Å. In the fifth O site, O is bonded in a 2-coordinate geometry to one Ba, one Al, and one C atom. In the sixth O site, O is bonded in a water-like geometry to two equivalent Al atoms. In the seventh O site, O is bonded in a 3-coordinate geometry to two equivalent Al and one O atom. In the eighth O site, O is bonded in a distorted single-bond geometry to three equivalent Ba and one C atom.