Materials Data on Cs2SiF6 by Materials Project
Cs2SiF6 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Cs1+ is bonded to twelve equivalent F1- atoms to form distorted CsF12 cuboctahedra that share corners with twelve equivalent CsF12 cuboctahedra, faces with six equivalent CsF12 cuboctahedra, and faces with four equivalent SiF6 octahedra. All Cs–F bond lengths are 3.25 Å. Si4+ is bonded to six equivalent F1- atoms to form SiF6 octahedra that share faces with eight equivalent CsF12 cuboctahedra. All Si–F bond lengths are 1.72 Å. F1- is bonded in a single-bond geometry to four equivalent Cs1+ and one Si4+ atom.