Materials Data on KCu3(AsO5)2 by Materials Project

Abstract

KCu3(AsO5)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. K1+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.75–3.25 Å. There are two inequivalent Cu3+ sites. In the first Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with four equivalent AsO4 tetrahedra and edges with four equivalent CuO6 octahedra. There are two shorter (1.88 Å) and four longer (2.19 Å) Cu–O bond lengths. In the second Cu3+ site, Cu3+ is bonded to six O2- atoms to form distorted CuO6 octahedra that share corners with four equivalent AsO4 tetrahedra and edges with four CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.84–2.47 Å. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 53–54°. There are a spread of As–O bond distances ranging from 1.69–1.78 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, two equivalent Cu3+, and one As5+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to two equivalent K1+ and one As5+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one K1+, two Cu3+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Cu3+ atoms.