Li4Fe3(NiO4)3 crystallizes in the triclinic P-1 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form LiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with five equivalent Ni(1)O6 octahedra,  an edgeedge with one Li(1)O6 octahedra,  an edgeedge with one Li(2)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, and edges with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-13°. In the second Li site, Li(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form LiO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with four equivalent Ni(2)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-14°. In the third Li site, Li(3) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form LiO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share  a cornercorner with one Li(3)O6 octahedra,  an edgeedge with one Li(2)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with three equivalent Li(1)O6 octahedra, and edges with three equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 9°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with four equivalent Li(3)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(3), one O(4), one O(6), and two equivalent O(5) atoms to form NiO6 octahedra that share  a cornercorner with one Li(2)O6 octahedra, corners with five equivalent Li(1)O6 octahedra,  an edgeedge with one Li(1)O6 octahedra,  an edgeedge with one Li(2)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, and edges with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-14°. In the second Ni site, Ni(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with two equivalent Li(1)O6 octahedra, corners with four equivalent Li(2)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-13°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), one Li(3), one Fe(1), one Fe(2), and one Ni(2) atom to form OLi2Fe2Ni square pyramids that share  a cornercorner with one O(4)Li2FeNi2 square pyramid,  a cornercorner with one O(5)Li2FeNi2 square pyramid, corners with two equivalent O(6)Li2Fe2Ni square pyramids, corners with four equivalent O(1)Li2Fe2Ni square pyramids, edges with four equivalent O(3)Li3FeNi2 octahedra,  an edgeedge with one O(6)Li2Fe2Ni square pyramid,  an edgeedge with one O(4)Li2FeNi2 square pyramid, and  an edgeedge with one O(5)Li2FeNi2 square pyramid. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Li(1), one Fe(1), one Fe(2), and one Ni(1) atom. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Li(3), one Fe(2), one Ni(1), and one Ni(2) atom to form OLi3FeNi2 octahedra that share corners with four equivalent O(3)Li3FeNi2 octahedra,  a cornercorner with one O(4)Li2FeNi2 square pyramid,  a cornercorner with one O(5)Li2FeNi2 square pyramid, edges with two equivalent O(6)Li2Fe2Ni square pyramids, edges with two equivalent O(4)Li2FeNi2 square pyramids, edges with two equivalent O(5)Li2FeNi2 square pyramids, and edges with four equivalent O(1)Li2Fe2Ni square pyramids. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded to two equivalent Li(1), one Fe(1), one Ni(1), and one Ni(2) atom to form OLi2FeNi2 square pyramids that share  a cornercorner with one O(3)Li3FeNi2 octahedra,  a cornercorner with one O(1)Li2Fe2Ni square pyramid,  a cornercorner with one O(6)Li2Fe2Ni square pyramid,  a cornercorner with one O(4)Li2FeNi2 square pyramid, corners with three equivalent O(5)Li2FeNi2 square pyramids, edges with two equivalent O(3)Li3FeNi2 octahedra,  an edgeedge with one O(1)Li2Fe2Ni square pyramid,  an edgeedge with one O(4)Li2FeNi2 square pyramid,  an edgeedge with one O(5)Li2FeNi2 square pyramid, and edges with two equivalent O(6)Li2Fe2Ni square pyramids. The corner-sharing octahedral tilt angles are 4°. In the fifth O site, O(5) is bonded to one Li(1), one Li(2), one Fe(1), and two equivalent Ni(1) atoms to form OLi2FeNi2 square pyramids that share  a cornercorner with one O(3)Li3FeNi2 octahedra,  a cornercorner with one O(1)Li2Fe2Ni square pyramid,  a cornercorner with one O(6)Li2Fe2Ni square pyramid,  a cornercorner with one O(5)Li2FeNi2 square pyramid, corners with three equivalent O(4)Li2FeNi2 square pyramids, edges with two equivalent O(3)Li3FeNi2 octahedra,  an edgeedge with one O(1)Li2Fe2Ni square pyramid,  an edgeedge with one O(4)Li2FeNi2 square pyramid,  an edgeedge with one O(5)Li2FeNi2 square pyramid, and edges with two equivalent O(6)Li2Fe2Ni square pyramids. The corner-sharing octahedral tilt angles are 3°. In the sixth O site, O(6) is bonded to one Li(1), one Li(3), two equivalent Fe(1), and one Ni(1) atom to form OLi2Fe2Ni square pyramids that share  a cornercorner with one O(6)Li2Fe2Ni square pyramid,  a cornercorner with one O(4)Li2FeNi2 square pyramid,  a cornercorner with one O(5)Li2FeNi2 square pyramid, corners with two equivalent O(1)Li2Fe2Ni square pyramids, edges with two equivalent O(3)Li3FeNi2 octahedra,  an edgeedge with one O(1)Li2Fe2Ni square pyramid,  an edgeedge with one O(6)Li2Fe2Ni square pyramid, edges with two equivalent O(4)Li2FeNi2 square pyramids, and edges with two equivalent O(5)Li2FeNi2 square pyramids.
Li4Fe3(NiO4)3 crystallizes in the triclinic P-1 space group. There are three inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), one O(5), one O(6), and two equivalent O(4) atoms to form LiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with five equivalent Ni(1)O6 octahedra,  an edgeedge with one Li(1)O6 octahedra,  an edgeedge with one Li(2)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, and edges with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-13°. The Li(1)-O(2) bond length is 2.07 Å. The Li(1)-O(3) bond length is 2.19 Å. The Li(1)-O(5) bond length is 2.16 Å. The Li(1)-O(6) bond length is 2.17 Å. There is one shorter (2.08 Å) and one longer (2.15 Å) Li(1)-O(4) bond length. In the second Li site, Li(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(5) atoms to form LiO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with four equivalent Ni(2)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-14°. Both Li(2)-O(1) bond lengths are 2.13 Å. Both Li(2)-O(3) bond lengths are 2.15 Å. Both Li(2)-O(5) bond lengths are 2.15 Å. In the third Li site, Li(3) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form LiO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. Both Li(3)-O(1) bond lengths are 2.08 Å. Both Li(3)-O(3) bond lengths are 2.28 Å. Both Li(3)-O(6) bond lengths are 2.16 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share  a cornercorner with one Li(3)O6 octahedra,  an edgeedge with one Li(2)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with three equivalent Li(1)O6 octahedra, and edges with three equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 9°. The Fe(1)-O(1) bond length is 1.93 Å. The Fe(1)-O(2) bond length is 1.93 Å. The Fe(1)-O(4) bond length is 1.89 Å. The Fe(1)-O(5) bond length is 1.90 Å. There is one shorter (1.94 Å) and one longer (2.00 Å) Fe(1)-O(6) bond length. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with four equivalent Li(3)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. Both Fe(2)-O(1) bond lengths are 2.10 Å. Both Fe(2)-O(2) bond lengths are 1.95 Å. Both Fe(2)-O(3) bond lengths are 1.95 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(3), one O(4), one O(6), and two equivalent O(5) atoms to form NiO6 octahedra that share  a cornercorner with one Li(2)O6 octahedra, corners with five equivalent Li(1)O6 octahedra,  an edgeedge with one Li(1)O6 octahedra,  an edgeedge with one Li(2)O6 octahedra,  an edgeedge with one Li(3)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, and edges with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-14°. The Ni(1)-O(2) bond length is 2.11 Å. The Ni(1)-O(3) bond length is 2.04 Å. The Ni(1)-O(4) bond length is 2.04 Å. The Ni(1)-O(6) bond length is 2.12 Å. There is one shorter (2.02 Å) and one longer (2.04 Å) Ni(1)-O(5) bond length. In the second Ni site, Ni(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with two equivalent Li(1)O6 octahedra, corners with four equivalent Li(2)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(3)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-13°. Both Ni(2)-O(1) bond lengths are 2.10 Å. Both Ni(2)-O(3) bond lengths are 2.03 Å. Both Ni(2)-O(4) bond lengths are 2.06 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), one Li(3), one Fe(1), one Fe(2), and one Ni(2) atom to form OLi2Fe2Ni square pyramids that share  a cornercorner with one O(4)Li2FeNi2 square pyramid,  a cornercorner with one O(5)Li2FeNi2 square pyramid, corners with two equivalent O(6)Li2Fe2Ni square pyramids, corners with four equivalent O(1)Li2Fe2Ni square pyramids, edges with four equivalent O(3)Li3FeNi2 octahedra,  an edgeedge with one O(6)Li2Fe2Ni square pyramid,  an edgeedge with one O(4)Li2FeNi2 square pyramid, and  an edgeedge with one O(5)Li2FeNi2 square pyramid. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Li(1), one Fe(1), one Fe(2), and one Ni(1) atom. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Li(3), one Fe(2), one Ni(1), and one Ni(2) atom to form OLi3FeNi2 octahedra that share corners with four equivalent O(3)Li3FeNi2 octahedra,  a cornercorner with one O(4)Li2FeNi2 square pyramid,  a cornercorner with one O(5)Li2FeNi2 square pyramid, edges with two equivalent O(6)Li2Fe2Ni square pyramids, edges with two equivalent O(4)Li2FeNi2 square pyramids, edges with two equivalent O(5)Li2FeNi2 square pyramids, and edges with four equivalent O(1)Li2Fe2Ni square pyramids. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded to two equivalent Li(1), one Fe(1), one Ni(1), and one Ni(2) atom to form OLi2FeNi2 square pyramids that share  a cornercorner with one O(3)Li3FeNi2 octahedra,  a cornercorner with one O(1)Li2Fe2Ni square pyramid,  a cornercorner with one O(6)Li2Fe2Ni square pyramid,  a cornercorner with one O(4)Li2FeNi2 square pyramid, corners with three equivalent O(5)Li2FeNi2 square pyramids, edges with two equivalent O(3)Li3FeNi2 octahedra,  an edgeedge with one O(1)Li2Fe2Ni square pyramid,  an edgeedge with one O(4)Li2FeNi2 square pyramid,  an edgeedge with one O(5)Li2FeNi2 square pyramid, and edges with two equivalent O(6)Li2Fe2Ni square pyramids. The corner-sharing octahedral tilt angles are 4°. In the fifth O site, O(5) is bonded to one Li(1), one Li(2), one Fe(1), and two equivalent Ni(1) atoms to form OLi2FeNi2 square pyramids that share  a cornercorner with one O(3)Li3FeNi2 octahedra,  a cornercorner with one O(1)Li2Fe2Ni square pyramid,  a cornercorner with one O(6)Li2Fe2Ni square pyramid,  a cornercorner with one O(5)Li2FeNi2 square pyramid, corners with three equivalent O(4)Li2FeNi2 square pyramids, edges with two equivalent O(3)Li3FeNi2 octahedra,  an edgeedge with one O(1)Li2Fe2Ni square pyramid,  an edgeedge with one O(4)Li2FeNi2 square pyramid,  an edgeedge with one O(5)Li2FeNi2 square pyramid, and edges with two equivalent O(6)Li2Fe2Ni square pyramids. The corner-sharing octahedral tilt angles are 3°. In the sixth O site, O(6) is bonded to one Li(1), one Li(3), two equivalent Fe(1), and one Ni(1) atom to form OLi2Fe2Ni square pyramids that share  a cornercorner with one O(6)Li2Fe2Ni square pyramid,  a cornercorner with one O(4)Li2FeNi2 square pyramid,  a cornercorner with one O(5)Li2FeNi2 square pyramid, corners with two equivalent O(1)Li2Fe2Ni square pyramids, edges with two equivalent O(3)Li3FeNi2 octahedra,  an edgeedge with one O(1)Li2Fe2Ni square pyramid,  an edgeedge with one O(6)Li2Fe2Ni square pyramid, edges with two equivalent O(4)Li2FeNi2 square pyramids, and edges with two equivalent O(5)Li2FeNi2 square pyramids.