Materials Data on Rb2CuF4 by Materials Project

Abstract

Rb2CuF4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Rb1+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Rb–F bond distances ranging from 2.87–3.00 Å. Cu2+ is bonded to six F1- atoms to form corner-sharing CuF6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (1.98 Å) and four longer (2.12 Å) Cu–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to four equivalent Rb1+ and two equivalent Cu2+ atoms to form a mixture of distorted corner, edge, and face-sharing FRb4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–58°. In the second F1- site, F1- is bonded to five equivalent Rb1+ and one Cu2+ atom to form distorted FRb5Cu octahedra that share corners with seventeen FRb4Cu2 octahedra, edges with eight equivalent FRb5Cu octahedra, and faces with four equivalent FRb4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–58°.