Materials Data on Cs2CaF4 by Materials Project
Cs2CaF4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Cs1+ is bonded in a 9-coordinate geometry to nine F1- atoms. There are a spread of Cs–F bond distances ranging from 3.00–3.23 Å. Ca2+ is bonded to six F1- atoms to form corner-sharing CaF6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ca–F bond lengths are 2.28 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to five equivalent Cs1+ and one Ca2+ atom to form a mixture of distorted edge and corner-sharing FCs5Ca octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second F1- site, F1- is bonded in a distorted linear geometry to four equivalent Cs1+ and two equivalent Ca2+ atoms.