Materials Data on Cs3SiF7 by Materials Project
Cs3SiF7 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 10-coordinate geometry to ten F1- atoms. There are a spread of Cs–F bond distances ranging from 3.07–3.25 Å. In the second Cs1+ site, Cs1+ is bonded to six F1- atoms to form CsF6 octahedra that share corners with four equivalent SiF6 octahedra and corners with six equivalent CsF6 octahedra. The corner-sharing octahedra tilt angles range from 0–67°. There are two shorter (3.12 Å) and four longer (3.26 Å) Cs–F bond lengths. Si4+ is bonded to six F1- atoms to form SiF6 octahedra that share corners with four equivalent CsF6 octahedra. The corner-sharing octahedral tilt angles are 67°. There is two shorter (1.72 Å) and four longer (1.73 Å) Si–F bond length. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to three equivalent Cs1+ and one Si4+ atom. In the second F1- site, F1- is bonded to six Cs1+ atoms to form corner-sharing FCs6 octahedra. The corner-sharing octahedra tilt angles range from 0–25°. In the third F1- site, F1- is bonded in a single-bond geometry to four Cs1+ and one Si4+ atom.