Fe3F8(H2O)2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1) and four equivalent F(1) atoms to form corner-sharing FeO2F4 octahedra. The corner-sharing octahedral tilt angles are 40°. In the second Fe site, Fe(2) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form FeF6 octahedra that share corners with two equivalent Fe(1)O2F4 octahedra and corners with four equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 20-40°. H(1) is bonded in a single-bond geometry to one O(1) atom. O(1) is bonded in a distorted water-like geometry to one Fe(1) and two equivalent H(1) atoms. There are three inequivalent F sites. In the first F site, F(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(2) atom. In the second F site, F(2) is bonded in a bent 150 degrees geometry to two equivalent Fe(2) atoms. In the third F site, F(3) is bonded in a bent 150 degrees geometry to two equivalent Fe(2) atoms.
Fe3F8(H2O)2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1) and four equivalent F(1) atoms to form corner-sharing FeO2F4 octahedra. The corner-sharing octahedral tilt angles are 40°. Both Fe(1)-O(1) bond lengths are 2.12 Å. All Fe(1)-F(1) bond lengths are 2.12 Å. In the second Fe site, Fe(2) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form FeF6 octahedra that share corners with two equivalent Fe(1)O2F4 octahedra and corners with four equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 20-40°. Both Fe(2)-F(1) bond lengths are 1.95 Å. Both Fe(2)-F(2) bond lengths are 1.97 Å. Both Fe(2)-F(3) bond lengths are 1.96 Å. H(1) is bonded in a single-bond geometry to one O(1) atom. The H(1)-O(1) bond length is 0.99 Å. O(1) is bonded in a distorted water-like geometry to one Fe(1) and two equivalent H(1) atoms. There are three inequivalent F sites. In the first F site, F(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(2) atom. In the second F site, F(2) is bonded in a bent 150 degrees geometry to two equivalent Fe(2) atoms. In the third F site, F(3) is bonded in a bent 150 degrees geometry to two equivalent Fe(2) atoms.