Li2Fe4OF8 is Ilmenite-derived structured and crystallizes in the monoclinic Cc space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(1), one F(3), one F(5), one F(6), one F(7), and one F(8) atom to form LiF6 octahedra that share corners with three equivalent Fe(1)OF5 octahedra, corners with three equivalent Fe(2)OF5 octahedra, corners with three equivalent Fe(4)OF5 pentagonal pyramids, and edges with three equivalent Fe(3)F6 octahedra. The corner-sharing octahedral tilt angles range from 45-65°. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(1), one F(1), one F(2), one F(3), one F(4), and one F(6) atom. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one F(1), one F(2), one F(3), one F(4), and one F(6) atom to form FeOF5 octahedra that share corners with three equivalent Li(1)F6 octahedra, corners with three equivalent Fe(3)F6 octahedra, corners with three equivalent Fe(4)OF5 pentagonal pyramids, and  a faceface with one Fe(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 45-65°. In the second Fe site, Fe(2) is bonded to one O(1), one F(2), one F(4), one F(5), one F(7), and one F(8) atom to form FeOF5 octahedra that share corners with three equivalent Li(1)F6 octahedra, corners with three equivalent Fe(3)F6 octahedra, edges with three equivalent Fe(4)OF5 pentagonal pyramids, and  a faceface with one Fe(1)OF5 octahedra. The corner-sharing octahedral tilt angles range from 44-65°. In the third Fe site, Fe(3) is bonded to one F(1), one F(3), one F(5), one F(6), one F(7), and one F(8) atom to form FeF6 octahedra that share corners with three equivalent Fe(1)OF5 octahedra, corners with three equivalent Fe(2)OF5 octahedra, edges with three equivalent Li(1)F6 octahedra, and  a faceface with one Fe(4)OF5 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 44-65°. In the fourth Fe site, Fe(4) is bonded to one O(1), one F(2), one F(4), one F(5), one F(7), and one F(8) atom to form distorted FeOF5 pentagonal pyramids that share corners with three equivalent Li(1)F6 octahedra, corners with three equivalent Fe(1)OF5 octahedra, edges with three equivalent Fe(2)OF5 octahedra, and  a faceface with one Fe(3)F6 octahedra. The corner-sharing octahedral tilt angles range from 43-52°. O(1) is bonded to one Li(2), one Fe(1), one Fe(2), and one Fe(4) atom to form distorted OLiFe3 trigonal pyramids that share  an edgeedge with one F(1)Li2Fe2 trigonal pyramid and  an edgeedge with one F(7)LiFe3 trigonal pyramid. There are eight inequivalent F sites. In the first F site, F(3) is bonded in a 4-coordinate geometry to one Li(1), one Li(2), one Fe(1), and one Fe(3) atom. In the second F site, F(4) is bonded in a 4-coordinate geometry to one Li(2), one Fe(1), one Fe(2), and one Fe(4) atom. In the third F site, F(5) is bonded in a rectangular see-saw-like geometry to one Li(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the fourth F site, F(6) is bonded in a distorted see-saw-like geometry to one Li(1), one Li(2), one Fe(1), and one Fe(3) atom. In the fifth F site, F(7) is bonded to one Li(1), one Fe(2), one Fe(3), and one Fe(4) atom to form distorted FLiFe3 trigonal pyramids that share  an edgeedge with one O(1)LiFe3 trigonal pyramid and  an edgeedge with one F(1)Li2Fe2 trigonal pyramid. In the sixth F site, F(8) is bonded in a distorted see-saw-like geometry to one Li(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the seventh F site, F(1) is bonded to one Li(1), one Li(2), one Fe(1), and one Fe(3) atom to form distorted FLi2Fe2 trigonal pyramids that share  an edgeedge with one O(1)LiFe3 trigonal pyramid and  an edgeedge with one F(7)LiFe3 trigonal pyramid. In the eighth F site, F(2) is bonded in a 4-coordinate geometry to one Li(2), one Fe(1), one Fe(2), and one Fe(4) atom.
Li2Fe4OF8 is Ilmenite-derived structured and crystallizes in the monoclinic Cc space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one F(1), one F(3), one F(5), one F(6), one F(7), and one F(8) atom to form LiF6 octahedra that share corners with three equivalent Fe(1)OF5 octahedra, corners with three equivalent Fe(2)OF5 octahedra, corners with three equivalent Fe(4)OF5 pentagonal pyramids, and edges with three equivalent Fe(3)F6 octahedra. The corner-sharing octahedral tilt angles range from 45-65°. The Li(1)-F(1) bond length is 2.07 Å. The Li(1)-F(3) bond length is 2.17 Å. The Li(1)-F(5) bond length is 2.14 Å. The Li(1)-F(6) bond length is 2.09 Å. The Li(1)-F(7) bond length is 2.04 Å. The Li(1)-F(8) bond length is 2.13 Å. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(1), one F(1), one F(2), one F(3), one F(4), and one F(6) atom. The Li(2)-O(1) bond length is 2.01 Å. The Li(2)-F(1) bond length is 2.19 Å. The Li(2)-F(2) bond length is 1.99 Å. The Li(2)-F(3) bond length is 2.45 Å. The Li(2)-F(4) bond length is 1.99 Å. The Li(2)-F(6) bond length is 2.32 Å. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one F(1), one F(2), one F(3), one F(4), and one F(6) atom to form FeOF5 octahedra that share corners with three equivalent Li(1)F6 octahedra, corners with three equivalent Fe(3)F6 octahedra, corners with three equivalent Fe(4)OF5 pentagonal pyramids, and  a faceface with one Fe(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 45-65°. The Fe(1)-O(1) bond length is 2.02 Å. The Fe(1)-F(1) bond length is 2.11 Å. The Fe(1)-F(2) bond length is 2.30 Å. The Fe(1)-F(3) bond length is 2.08 Å. The Fe(1)-F(4) bond length is 2.21 Å. The Fe(1)-F(6) bond length is 2.14 Å. In the second Fe site, Fe(2) is bonded to one O(1), one F(2), one F(4), one F(5), one F(7), and one F(8) atom to form FeOF5 octahedra that share corners with three equivalent Li(1)F6 octahedra, corners with three equivalent Fe(3)F6 octahedra, edges with three equivalent Fe(4)OF5 pentagonal pyramids, and  a faceface with one Fe(1)OF5 octahedra. The corner-sharing octahedral tilt angles range from 44-65°. The Fe(2)-O(1) bond length is 2.02 Å. The Fe(2)-F(2) bond length is 2.18 Å. The Fe(2)-F(4) bond length is 2.33 Å. The Fe(2)-F(5) bond length is 2.07 Å. The Fe(2)-F(7) bond length is 2.15 Å. The Fe(2)-F(8) bond length is 2.16 Å. In the third Fe site, Fe(3) is bonded to one F(1), one F(3), one F(5), one F(6), one F(7), and one F(8) atom to form FeF6 octahedra that share corners with three equivalent Fe(1)OF5 octahedra, corners with three equivalent Fe(2)OF5 octahedra, edges with three equivalent Li(1)F6 octahedra, and  a faceface with one Fe(4)OF5 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 44-65°. The Fe(3)-F(1) bond length is 2.09 Å. The Fe(3)-F(3) bond length is 2.07 Å. The Fe(3)-F(5) bond length is 2.21 Å. The Fe(3)-F(6) bond length is 2.04 Å. The Fe(3)-F(7) bond length is 2.14 Å. The Fe(3)-F(8) bond length is 2.17 Å. In the fourth Fe site, Fe(4) is bonded to one O(1), one F(2), one F(4), one F(5), one F(7), and one F(8) atom to form distorted FeOF5 pentagonal pyramids that share corners with three equivalent Li(1)F6 octahedra, corners with three equivalent Fe(1)OF5 octahedra, edges with three equivalent Fe(2)OF5 octahedra, and  a faceface with one Fe(3)F6 octahedra. The corner-sharing octahedral tilt angles range from 43-52°. The Fe(4)-O(1) bond length is 1.96 Å. The Fe(4)-F(2) bond length is 2.13 Å. The Fe(4)-F(4) bond length is 2.07 Å. The Fe(4)-F(5) bond length is 2.35 Å. The Fe(4)-F(7) bond length is 2.27 Å. The Fe(4)-F(8) bond length is 2.24 Å. O(1) is bonded to one Li(2), one Fe(1), one Fe(2), and one Fe(4) atom to form distorted OLiFe3 trigonal pyramids that share  an edgeedge with one F(1)Li2Fe2 trigonal pyramid and  an edgeedge with one F(7)LiFe3 trigonal pyramid. There are eight inequivalent F sites. In the first F site, F(3) is bonded in a 4-coordinate geometry to one Li(1), one Li(2), one Fe(1), and one Fe(3) atom. In the second F site, F(4) is bonded in a 4-coordinate geometry to one Li(2), one Fe(1), one Fe(2), and one Fe(4) atom. In the third F site, F(5) is bonded in a rectangular see-saw-like geometry to one Li(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the fourth F site, F(6) is bonded in a distorted see-saw-like geometry to one Li(1), one Li(2), one Fe(1), and one Fe(3) atom. In the fifth F site, F(7) is bonded to one Li(1), one Fe(2), one Fe(3), and one Fe(4) atom to form distorted FLiFe3 trigonal pyramids that share  an edgeedge with one O(1)LiFe3 trigonal pyramid and  an edgeedge with one F(1)Li2Fe2 trigonal pyramid. In the sixth F site, F(8) is bonded in a distorted see-saw-like geometry to one Li(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the seventh F site, F(1) is bonded to one Li(1), one Li(2), one Fe(1), and one Fe(3) atom to form distorted FLi2Fe2 trigonal pyramids that share  an edgeedge with one O(1)LiFe3 trigonal pyramid and  an edgeedge with one F(7)LiFe3 trigonal pyramid. In the eighth F site, F(2) is bonded in a 4-coordinate geometry to one Li(2), one Fe(1), one Fe(2), and one Fe(4) atom.