Materials Data on K4C2O9 by Materials Project
K4C2O9 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded in a 6-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.79–3.13 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.76–2.80 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.75–3.09 Å. C is bonded in a trigonal planar geometry to three O atoms. There are a spread of C–O bond distances ranging from 1.28–1.31 Å. There are five inequivalent O sites. In the first O site, O is bonded to four K atoms to form a mixture of distorted edge and corner-sharing OK4 trigonal pyramids. In the second O site, O is bonded to four equivalent K atoms to form a mixture of distorted edge and corner-sharing OK4 trigonal pyramids. In the third O site, O is bonded in a distorted single-bond geometry to four K and one C atom. In the fourth O site, O is bonded in a distorted single-bond geometry to four K and one C atom. In the fifth O site, O is bonded in a single-bond geometry to two K and one C atom.