Materials Data on K2Cr2Cu(PO7)2 by Materials Project
K2Cr2Cu(PO7)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. K is bonded in a 10-coordinate geometry to ten O atoms. There are a spread of K–O bond distances ranging from 2.82–3.29 Å. Cr is bonded to four O atoms to form CrO4 tetrahedra that share a cornercorner with one PO4 tetrahedra. There are a spread of Cr–O bond distances ranging from 1.61–1.86 Å. Cu is bonded in a distorted square co-planar geometry to four O atoms. There is two shorter (1.88 Å) and two longer (1.90 Å) Cu–O bond length. P is bonded to four O atoms to form PO4 tetrahedra that share a cornercorner with one CrO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.58 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a distorted bent 120 degrees geometry to one K, one Cu, and one P atom. In the second O site, O is bonded in a bent 150 degrees geometry to one Cu and one P atom. In the third O site, O is bonded in a distorted bent 120 degrees geometry to one K, one Cr, and one P atom. In the fourth O site, O is bonded in a distorted single-bond geometry to two equivalent K and one Cr atom. In the fifth O site, O is bonded in a distorted single-bond geometry to two equivalent K and one Cr atom. In the sixth O site, O is bonded in a single-bond geometry to two equivalent K and one Cr atom. In the seventh O site, O is bonded in a single-bond geometry to two equivalent K and one P atom.