Li3Fe3OF7 crystallizes in the monoclinic Pm space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), one F(1), and one F(6) atom to form distorted LiO2F2 trigonal pyramids that share  a cornercorner with one Li(2)F6 octahedra, corners with two equivalent Fe(3)OF5 octahedra, corners with three equivalent Fe(1)O2F4 octahedra, corners with two equivalent Li(1)O2F2 trigonal pyramids,  an edgeedge with one Fe(1)O2F4 octahedra, and edges with two equivalent Fe(3)OF5 octahedra. The corner-sharing octahedral tilt angles range from 13-71°. In the second Li site, Li(2) is bonded to one F(1), one F(5), two equivalent F(2), and two equivalent F(4) atoms to form distorted LiF6 octahedra that share corners with four equivalent Fe(3)OF5 octahedra,  a cornercorner with one Li(1)O2F2 trigonal pyramid, edges with two equivalent Li(2)F6 octahedra, and edges with two equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 47-53°. In the third Li site, Li(3) is bonded in a rectangular see-saw-like geometry to one F(2), one F(4), and two equivalent F(5) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), one F(3), one F(6), and two equivalent F(7) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(2)F6 octahedra, corners with three equivalent Li(1)O2F2 trigonal pyramids, edges with two equivalent Fe(1)O2F4 octahedra, edges with two equivalent Fe(3)OF5 octahedra, and  an edgeedge with one Li(1)O2F2 trigonal pyramid. The corner-sharing octahedral tilt angles range from 47-50°. In the second Fe site, Fe(2) is bonded to one F(2), one F(7), two equivalent F(3), and two equivalent F(5) atoms to form FeF6 octahedra that share corners with four equivalent Fe(1)O2F4 octahedra, edges with two equivalent Li(2)F6 octahedra, and edges with two equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 47-50°. In the third Fe site, Fe(3) is bonded to one O(1), one F(4), two equivalent F(1), and two equivalent F(6) atoms to form FeOF5 octahedra that share corners with four equivalent Li(2)F6 octahedra, corners with two equivalent Li(1)O2F2 trigonal pyramids, edges with two equivalent Fe(1)O2F4 octahedra, edges with two equivalent Fe(3)OF5 octahedra, and edges with two equivalent Li(1)O2F2 trigonal pyramids. The corner-sharing octahedral tilt angles range from 47-53°. O(1) is bonded to two equivalent Li(1), one Fe(3), and two equivalent Fe(1) atoms to form edge-sharing OLi2Fe3 square pyramids. There are seven inequivalent F sites. In the first F site, F(1) is bonded in a rectangular see-saw-like geometry to one Li(1), one Li(2), and two equivalent Fe(3) atoms. In the second F site, F(2) is bonded to one Li(3), two equivalent Li(2), and one Fe(2) atom to form distorted FLi3Fe tetrahedra that share corners with two equivalent F(5)Li3Fe2 square pyramids, corners with two equivalent F(2)Li3Fe tetrahedra, and edges with two equivalent F(5)Li3Fe2 square pyramids. In the third F site, F(3) is bonded in a distorted trigonal planar geometry to one Fe(1) and two equivalent Fe(2) atoms. In the fourth F site, F(4) is bonded in a rectangular see-saw-like geometry to one Li(3), two equivalent Li(2), and one Fe(3) atom. In the fifth F site, F(5) is bonded to one Li(2), two equivalent Li(3), and two equivalent Fe(2) atoms to form FLi3Fe2 square pyramids that share corners with two equivalent F(2)Li3Fe tetrahedra, edges with two equivalent F(5)Li3Fe2 square pyramids, and edges with two equivalent F(2)Li3Fe tetrahedra. In the sixth F site, F(6) is bonded in a rectangular see-saw-like geometry to one Li(1), one Fe(1), and two equivalent Fe(3) atoms. In the seventh F site, F(7) is bonded in a distorted T-shaped geometry to one Fe(2) and two equivalent Fe(1) atoms.
Li3Fe3OF7 crystallizes in the monoclinic Pm space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), one F(1), and one F(6) atom to form distorted LiO2F2 trigonal pyramids that share  a cornercorner with one Li(2)F6 octahedra, corners with two equivalent Fe(3)OF5 octahedra, corners with three equivalent Fe(1)O2F4 octahedra, corners with two equivalent Li(1)O2F2 trigonal pyramids,  an edgeedge with one Fe(1)O2F4 octahedra, and edges with two equivalent Fe(3)OF5 octahedra. The corner-sharing octahedral tilt angles range from 13-71°. Both Li(1)-O(1) bond lengths are 2.01 Å. The Li(1)-F(1) bond length is 2.03 Å. The Li(1)-F(6) bond length is 1.83 Å. In the second Li site, Li(2) is bonded to one F(1), one F(5), two equivalent F(2), and two equivalent F(4) atoms to form distorted LiF6 octahedra that share corners with four equivalent Fe(3)OF5 octahedra,  a cornercorner with one Li(1)O2F2 trigonal pyramid, edges with two equivalent Li(2)F6 octahedra, and edges with two equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 47-53°. The Li(2)-F(1) bond length is 1.97 Å. The Li(2)-F(5) bond length is 2.23 Å. Both Li(2)-F(2) bond lengths are 2.10 Å. Both Li(2)-F(4) bond lengths are 2.15 Å. In the third Li site, Li(3) is bonded in a rectangular see-saw-like geometry to one F(2), one F(4), and two equivalent F(5) atoms. The Li(3)-F(2) bond length is 1.86 Å. The Li(3)-F(4) bond length is 1.91 Å. Both Li(3)-F(5) bond lengths are 2.06 Å. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), one F(3), one F(6), and two equivalent F(7) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(2)F6 octahedra, corners with three equivalent Li(1)O2F2 trigonal pyramids, edges with two equivalent Fe(1)O2F4 octahedra, edges with two equivalent Fe(3)OF5 octahedra, and  an edgeedge with one Li(1)O2F2 trigonal pyramid. The corner-sharing octahedral tilt angles range from 47-50°. Both Fe(1)-O(1) bond lengths are 2.06 Å. The Fe(1)-F(3) bond length is 2.22 Å. The Fe(1)-F(6) bond length is 2.28 Å. Both Fe(1)-F(7) bond lengths are 2.15 Å. In the second Fe site, Fe(2) is bonded to one F(2), one F(7), two equivalent F(3), and two equivalent F(5) atoms to form FeF6 octahedra that share corners with four equivalent Fe(1)O2F4 octahedra, edges with two equivalent Li(2)F6 octahedra, and edges with two equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 47-50°. The Fe(2)-F(2) bond length is 2.09 Å. The Fe(2)-F(7) bond length is 2.08 Å. Both Fe(2)-F(3) bond lengths are 2.06 Å. Both Fe(2)-F(5) bond lengths are 2.23 Å. In the third Fe site, Fe(3) is bonded to one O(1), one F(4), two equivalent F(1), and two equivalent F(6) atoms to form FeOF5 octahedra that share corners with four equivalent Li(2)F6 octahedra, corners with two equivalent Li(1)O2F2 trigonal pyramids, edges with two equivalent Fe(1)O2F4 octahedra, edges with two equivalent Fe(3)OF5 octahedra, and edges with two equivalent Li(1)O2F2 trigonal pyramids. The corner-sharing octahedral tilt angles range from 47-53°. The Fe(3)-O(1) bond length is 1.99 Å. The Fe(3)-F(4) bond length is 2.04 Å. Both Fe(3)-F(1) bond lengths are 2.18 Å. Both Fe(3)-F(6) bond lengths are 2.17 Å. O(1) is bonded to two equivalent Li(1), one Fe(3), and two equivalent Fe(1) atoms to form edge-sharing OLi2Fe3 square pyramids. There are seven inequivalent F sites. In the first F site, F(1) is bonded in a rectangular see-saw-like geometry to one Li(1), one Li(2), and two equivalent Fe(3) atoms. In the second F site, F(2) is bonded to one Li(3), two equivalent Li(2), and one Fe(2) atom to form distorted FLi3Fe tetrahedra that share corners with two equivalent F(5)Li3Fe2 square pyramids, corners with two equivalent F(2)Li3Fe tetrahedra, and edges with two equivalent F(5)Li3Fe2 square pyramids. In the third F site, F(3) is bonded in a distorted trigonal planar geometry to one Fe(1) and two equivalent Fe(2) atoms. In the fourth F site, F(4) is bonded in a rectangular see-saw-like geometry to one Li(3), two equivalent Li(2), and one Fe(3) atom. In the fifth F site, F(5) is bonded to one Li(2), two equivalent Li(3), and two equivalent Fe(2) atoms to form FLi3Fe2 square pyramids that share corners with two equivalent F(2)Li3Fe tetrahedra, edges with two equivalent F(5)Li3Fe2 square pyramids, and edges with two equivalent F(2)Li3Fe tetrahedra. In the sixth F site, F(6) is bonded in a rectangular see-saw-like geometry to one Li(1), one Fe(1), and two equivalent Fe(3) atoms. In the seventh F site, F(7) is bonded in a distorted T-shaped geometry to one Fe(2) and two equivalent Fe(1) atoms.