Li2FeO2F is Caswellsilverite-derived structured and crystallizes in the monoclinic C2/c space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form LiO4F2 octahedra that share corners with two equivalent Li(3)O4F2 octahedra, corners with two equivalent Fe(1)O4F2 octahedra, corners with two equivalent Fe(2)O4F2 octahedra, edges with two equivalent Li(3)O4F2 octahedra, edges with two equivalent Fe(1)O4F2 octahedra, edges with two equivalent Fe(2)O4F2 octahedra, edges with three equivalent Li(1)O4F2 octahedra, and edges with three equivalent Li(2)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 1-18°. In the second Li site, Li(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form LiO4F2 octahedra that share corners with two equivalent Li(3)O4F2 octahedra, corners with two equivalent Fe(1)O4F2 octahedra, corners with two equivalent Fe(2)O4F2 octahedra, edges with two equivalent Li(3)O4F2 octahedra, edges with two equivalent Fe(1)O4F2 octahedra, edges with two equivalent Fe(2)O4F2 octahedra, and edges with six equivalent Li(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the third Li site, Li(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form LiO4F2 octahedra that share corners with two equivalent Li(2)O4F2 octahedra, corners with four equivalent Li(1)O4F2 octahedra, edges with two equivalent Li(2)O4F2 octahedra, edges with three equivalent Fe(1)O4F2 octahedra, edges with three equivalent Fe(2)O4F2 octahedra, and edges with four equivalent Li(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 1-12°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form FeO4F2 octahedra that share corners with two equivalent Li(2)O4F2 octahedra, corners with four equivalent Li(1)O4F2 octahedra, edges with two equivalent Li(2)O4F2 octahedra, edges with three equivalent Li(3)O4F2 octahedra, edges with three equivalent Fe(2)O4F2 octahedra, and edges with four equivalent Li(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form FeO4F2 octahedra that share corners with two equivalent Li(2)O4F2 octahedra, corners with four equivalent Li(1)O4F2 octahedra, edges with two equivalent Li(2)O4F2 octahedra, edges with three equivalent Li(3)O4F2 octahedra, edges with three equivalent Fe(1)O4F2 octahedra, and edges with four equivalent Li(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 1-18°. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and one Fe(2) atom to form OLi4Fe2 octahedra that share corners with two equivalent O(1)Li4Fe2 octahedra, corners with two equivalent O(2)Li4Fe2 octahedra, corners with two equivalent F(1)Li4Fe2 octahedra, edges with two equivalent O(1)Li4Fe2 octahedra, edges with five equivalent O(2)Li4Fe2 octahedra, and edges with five equivalent F(1)Li4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-18°. In the second O site, O(2) is bonded to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and one Fe(2) atom to form OLi4Fe2 octahedra that share corners with two equivalent O(1)Li4Fe2 octahedra, corners with two equivalent O(2)Li4Fe2 octahedra, corners with two equivalent F(1)Li4Fe2 octahedra, edges with two equivalent O(2)Li4Fe2 octahedra, edges with five equivalent O(1)Li4Fe2 octahedra, and edges with five equivalent F(1)Li4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-15°. F(1) is bonded to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and one Fe(2) atom to form FLi4Fe2 octahedra that share corners with two equivalent O(1)Li4Fe2 octahedra, corners with two equivalent O(2)Li4Fe2 octahedra, corners with two equivalent F(1)Li4Fe2 octahedra, edges with two equivalent F(1)Li4Fe2 octahedra, edges with five equivalent O(1)Li4Fe2 octahedra, and edges with five equivalent O(2)Li4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°.
Li2FeO2F is Caswellsilverite-derived structured and crystallizes in the monoclinic C2/c space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form LiO4F2 octahedra that share corners with two equivalent Li(3)O4F2 octahedra, corners with two equivalent Fe(1)O4F2 octahedra, corners with two equivalent Fe(2)O4F2 octahedra, edges with two equivalent Li(3)O4F2 octahedra, edges with two equivalent Fe(1)O4F2 octahedra, edges with two equivalent Fe(2)O4F2 octahedra, edges with three equivalent Li(1)O4F2 octahedra, and edges with three equivalent Li(2)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 1-18°. There is one shorter (2.09 Å) and one longer (2.19 Å) Li(1)-O(1) bond length. There is one shorter (2.10 Å) and one longer (2.13 Å) Li(1)-O(2) bond length. Both Li(1)-F(1) bond lengths are 2.27 Å. In the second Li site, Li(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form LiO4F2 octahedra that share corners with two equivalent Li(3)O4F2 octahedra, corners with two equivalent Fe(1)O4F2 octahedra, corners with two equivalent Fe(2)O4F2 octahedra, edges with two equivalent Li(3)O4F2 octahedra, edges with two equivalent Fe(1)O4F2 octahedra, edges with two equivalent Fe(2)O4F2 octahedra, and edges with six equivalent Li(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. Both Li(2)-O(1) bond lengths are 2.08 Å. Both Li(2)-O(2) bond lengths are 2.16 Å. Both Li(2)-F(1) bond lengths are 2.09 Å. In the third Li site, Li(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form LiO4F2 octahedra that share corners with two equivalent Li(2)O4F2 octahedra, corners with four equivalent Li(1)O4F2 octahedra, edges with two equivalent Li(2)O4F2 octahedra, edges with three equivalent Fe(1)O4F2 octahedra, edges with three equivalent Fe(2)O4F2 octahedra, and edges with four equivalent Li(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 1-12°. Both Li(3)-O(1) bond lengths are 2.08 Å. Both Li(3)-O(2) bond lengths are 2.12 Å. Both Li(3)-F(1) bond lengths are 2.22 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form FeO4F2 octahedra that share corners with two equivalent Li(2)O4F2 octahedra, corners with four equivalent Li(1)O4F2 octahedra, edges with two equivalent Li(2)O4F2 octahedra, edges with three equivalent Li(3)O4F2 octahedra, edges with three equivalent Fe(2)O4F2 octahedra, and edges with four equivalent Li(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. Both Fe(1)-O(1) bond lengths are 1.99 Å. Both Fe(1)-O(2) bond lengths are 2.03 Å. Both Fe(1)-F(1) bond lengths are 2.09 Å. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(1) atoms to form FeO4F2 octahedra that share corners with two equivalent Li(2)O4F2 octahedra, corners with four equivalent Li(1)O4F2 octahedra, edges with two equivalent Li(2)O4F2 octahedra, edges with three equivalent Li(3)O4F2 octahedra, edges with three equivalent Fe(1)O4F2 octahedra, and edges with four equivalent Li(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 1-18°. Both Fe(2)-O(1) bond lengths are 2.01 Å. Both Fe(2)-O(2) bond lengths are 1.94 Å. Both Fe(2)-F(1) bond lengths are 2.26 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and one Fe(2) atom to form OLi4Fe2 octahedra that share corners with two equivalent O(1)Li4Fe2 octahedra, corners with two equivalent O(2)Li4Fe2 octahedra, corners with two equivalent F(1)Li4Fe2 octahedra, edges with two equivalent O(1)Li4Fe2 octahedra, edges with five equivalent O(2)Li4Fe2 octahedra, and edges with five equivalent F(1)Li4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-18°. In the second O site, O(2) is bonded to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and one Fe(2) atom to form OLi4Fe2 octahedra that share corners with two equivalent O(1)Li4Fe2 octahedra, corners with two equivalent O(2)Li4Fe2 octahedra, corners with two equivalent F(1)Li4Fe2 octahedra, edges with two equivalent O(2)Li4Fe2 octahedra, edges with five equivalent O(1)Li4Fe2 octahedra, and edges with five equivalent F(1)Li4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-15°. F(1) is bonded to one Li(2), one Li(3), two equivalent Li(1), one Fe(1), and one Fe(2) atom to form FLi4Fe2 octahedra that share corners with two equivalent O(1)Li4Fe2 octahedra, corners with two equivalent O(2)Li4Fe2 octahedra, corners with two equivalent F(1)Li4Fe2 octahedra, edges with two equivalent F(1)Li4Fe2 octahedra, edges with five equivalent O(1)Li4Fe2 octahedra, and edges with five equivalent O(2)Li4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°.