Materials Data on K2Cu(CO3)2 by Materials Project
K2Cu(CO3)2 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. K1+ is bonded to eight O2- atoms to form a mixture of distorted edge and corner-sharing KO8 hexagonal bipyramids. There are a spread of K–O bond distances ranging from 2.73–3.23 Å. Cu2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There is two shorter (1.96 Å) and two longer (1.97 Å) Cu–O bond length. C4+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.27 Å) and two longer (1.32 Å) C–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+, one Cu2+, and one C4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent K1+, one Cu2+, and one C4+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent K1+ and one C4+ atom.