Materials Data on KCuF3 by Materials Project

Abstract

KCuF3 is (Cubic) Perovskite structured and crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. K1+ is bonded to twelve F1- atoms to form KF12 cuboctahedra that share corners with twelve equivalent KF12 cuboctahedra, faces with six equivalent KF12 cuboctahedra, and faces with eight CuF6 octahedra. There are a spread of K–F bond distances ranging from 2.87–2.94 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to six F1- atoms to form CuF6 octahedra that share corners with six equivalent CuF6 octahedra and faces with eight equivalent KF12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Cu–F bond distances ranging from 1.96–2.20 Å. In the second Cu2+ site, Cu2+ is bonded to six F1- atoms to form CuF6 octahedra that share corners with six equivalent CuF6 octahedra and faces with eight equivalent KF12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Cu–F bond distances ranging from 1.95–2.19 Å. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a 6-coordinate geometry to four equivalent K1+ and two Cu2+ atoms. In the second F1- site, F1- is bonded in a distorted linear geometry to four equivalent K1+ and two Cu2+ atoms. In the third F1- site, F1- is bonded in a 2-coordinate geometry to four equivalent K1+ and two Cu2+ atoms.