Li3Cr2(FeO4)2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with six equivalent Fe(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-10°. In the second Li site, Li(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form LiO6 octahedra that share corners with six equivalent Cr(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CrO6 octahedra that share edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. In the second Cr site, Cr(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form CrO6 octahedra that share corners with six equivalent Li(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. Fe(1) 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 six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-10°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Cr(1), one Cr(2), and one Fe(1) atom to form OLi2Cr2Fe square pyramids that share corners with two equivalent O(2)Li2CrFe2 square pyramids, corners with seven equivalent O(1)Li2Cr2Fe square pyramids, edges with four equivalent O(3)Li3CrFe2 octahedra, edges with two equivalent O(1)Li2Cr2Fe square pyramids, and edges with two equivalent O(2)Li2CrFe2 square pyramids. In the second O site, O(2) is bonded to two equivalent Li(1), one Cr(1), and two equivalent Fe(1) atoms to form OLi2CrFe2 square pyramids that share corners with four equivalent O(1)Li2Cr2Fe square pyramids, corners with five equivalent O(2)Li2CrFe2 square pyramids, edges with four equivalent O(3)Li3CrFe2 octahedra, and edges with four equivalent O(1)Li2Cr2Fe square pyramids. In the third O site, O(3) is bonded to one Li(2), two equivalent Li(1), one Cr(2), and two equivalent Fe(1) atoms to form OLi3CrFe2 octahedra that share corners with six equivalent O(3)Li3CrFe2 octahedra, edges with four equivalent O(2)Li2CrFe2 square pyramids, and edges with eight equivalent O(1)Li2Cr2Fe square pyramids. The corner-sharing octahedra are not tilted.
Li3Cr2(FeO4)2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with six equivalent Fe(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-10°. Both Li(1)-O(1) bond lengths are 2.18 Å. Both Li(1)-O(2) bond lengths are 2.17 Å. Both Li(1)-O(3) bond lengths are 2.18 Å. In the second Li site, Li(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form LiO6 octahedra that share corners with six equivalent Cr(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. Both Li(2)-O(3) bond lengths are 2.18 Å. All Li(2)-O(1) bond lengths are 2.18 Å. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CrO6 octahedra that share edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. Both Cr(1)-O(2) bond lengths are 1.94 Å. All Cr(1)-O(1) bond lengths are 1.95 Å. In the second Cr site, Cr(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form CrO6 octahedra that share corners with six equivalent Li(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with four equivalent Li(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-9°. Both Cr(2)-O(3) bond lengths are 2.04 Å. All Cr(2)-O(1) bond lengths are 2.04 Å. Fe(1) 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 six equivalent Li(1)O6 octahedra, edges with two equivalent Li(1)O6 octahedra, edges with two equivalent Li(2)O6 octahedra, edges with two equivalent Cr(1)O6 octahedra, edges with two equivalent Cr(2)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-10°. Both Fe(1)-O(1) bond lengths are 2.05 Å. Both Fe(1)-O(2) bond lengths are 2.06 Å. Both Fe(1)-O(3) bond lengths are 2.04 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Cr(1), one Cr(2), and one Fe(1) atom to form OLi2Cr2Fe square pyramids that share corners with two equivalent O(2)Li2CrFe2 square pyramids, corners with seven equivalent O(1)Li2Cr2Fe square pyramids, edges with four equivalent O(3)Li3CrFe2 octahedra, edges with two equivalent O(1)Li2Cr2Fe square pyramids, and edges with two equivalent O(2)Li2CrFe2 square pyramids. In the second O site, O(2) is bonded to two equivalent Li(1), one Cr(1), and two equivalent Fe(1) atoms to form OLi2CrFe2 square pyramids that share corners with four equivalent O(1)Li2Cr2Fe square pyramids, corners with five equivalent O(2)Li2CrFe2 square pyramids, edges with four equivalent O(3)Li3CrFe2 octahedra, and edges with four equivalent O(1)Li2Cr2Fe square pyramids. In the third O site, O(3) is bonded to one Li(2), two equivalent Li(1), one Cr(2), and two equivalent Fe(1) atoms to form OLi3CrFe2 octahedra that share corners with six equivalent O(3)Li3CrFe2 octahedra, edges with four equivalent O(2)Li2CrFe2 square pyramids, and edges with eight equivalent O(1)Li2Cr2Fe square pyramids. The corner-sharing octahedra are not tilted.