CsFe2F6 crystallizes in the tetragonal I4_1/amd space group. Cs(1) is bonded to two equivalent F(2) and four equivalent F(1) atoms to form CsF6 octahedra that share corners with twelve equivalent Fe(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 68-69°. Fe(1) is bonded to two equivalent F(2) and four equivalent F(1) atoms to form FeF6 octahedra that share corners with six equivalent Cs(1)F6 octahedra and corners with six equivalent Fe(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 42-69°. There are two inequivalent F sites. In the first F site, F(2) is bonded in a 2-coordinate geometry to one Cs(1) and two equivalent Fe(1) atoms. In the second F site, F(1) is bonded in a 2-coordinate geometry to one Cs(1) and two equivalent Fe(1) atoms.
CsFe2F6 crystallizes in the tetragonal I4_1/amd space group. Cs(1) is bonded to two equivalent F(2) and four equivalent F(1) atoms to form CsF6 octahedra that share corners with twelve equivalent Fe(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 68-69°. Both Cs(1)-F(2) bond lengths are 3.16 Å. All Cs(1)-F(1) bond lengths are 3.20 Å. Fe(1) is bonded to two equivalent F(2) and four equivalent F(1) atoms to form FeF6 octahedra that share corners with six equivalent Cs(1)F6 octahedra and corners with six equivalent Fe(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 42-69°. Both Fe(1)-F(2) bond lengths are 1.98 Å. All Fe(1)-F(1) bond lengths are 1.98 Å. There are two inequivalent F sites. In the first F site, F(2) is bonded in a 2-coordinate geometry to one Cs(1) and two equivalent Fe(1) atoms. In the second F site, F(1) is bonded in a 2-coordinate geometry to one Cs(1) and two equivalent Fe(1) atoms.