Ca4MnFe3O10 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(5), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(5), two equivalent O(3), and two equivalent O(4) atoms. Mn(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with four equivalent Fe(2)O6 octahedra and corners with two equivalent Fe(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 16°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), and two equivalent O(5) atoms to form FeO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and corners with two equivalent Fe(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 38-44°. In the second Fe site, Fe(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with four equivalent Mn(1)O6 octahedra and corners with two equivalent Fe(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 16°. There are five inequivalent O sites. In the first O site, O(5) is bonded to one Ca(1), one Ca(2), and two equivalent Fe(1) atoms to form distorted corner-sharing OCa2Fe2 tetrahedra. In the second O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Mn(1), and one Fe(1) atom. In the third O site, O(2) is bonded in a 4-coordinate geometry to one Ca(2), two equivalent Ca(1), one Fe(1), and one Fe(2) atom. In the fourth O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one Mn(1), and one Fe(2) atom. In the fifth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one Mn(1), and one Fe(2) atom.
Ca4MnFe3O10 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(5), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. The Ca(1)-O(1) bond length is 2.31 Å. The Ca(1)-O(5) bond length is 2.37 Å. There is one shorter (2.51 Å) and one longer (3.02 Å) Ca(1)-O(2) bond length. There is one shorter (2.56 Å) and one longer (2.81 Å) Ca(1)-O(3) bond length. There is one shorter (2.46 Å) and one longer (2.52 Å) Ca(1)-O(4) bond length. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(5), two equivalent O(3), and two equivalent O(4) atoms. The Ca(2)-O(1) bond length is 2.49 Å. The Ca(2)-O(2) bond length is 2.34 Å. The Ca(2)-O(5) bond length is 2.37 Å. There is one shorter (2.46 Å) and one longer (2.50 Å) Ca(2)-O(3) bond length. There is one shorter (2.54 Å) and one longer (2.82 Å) Ca(2)-O(4) bond length. Mn(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with four equivalent Fe(2)O6 octahedra and corners with two equivalent Fe(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 16°. Both Mn(1)-O(1) bond lengths are 2.30 Å. Both Mn(1)-O(3) bond lengths are 1.95 Å. Both Mn(1)-O(4) bond lengths are 1.96 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), and two equivalent O(5) atoms to form FeO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and corners with two equivalent Fe(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 38-44°. The Fe(1)-O(1) bond length is 1.85 Å. The Fe(1)-O(2) bond length is 1.89 Å. There is one shorter (1.95 Å) and one longer (1.97 Å) Fe(1)-O(5) bond length. In the second Fe site, Fe(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with four equivalent Mn(1)O6 octahedra and corners with two equivalent Fe(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 16°. Both Fe(2)-O(2) bond lengths are 2.12 Å. Both Fe(2)-O(3) bond lengths are 2.00 Å. Both Fe(2)-O(4) bond lengths are 1.99 Å. There are five inequivalent O sites. In the first O site, O(5) is bonded to one Ca(1), one Ca(2), and two equivalent Fe(1) atoms to form distorted corner-sharing OCa2Fe2 tetrahedra. In the second O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Mn(1), and one Fe(1) atom. In the third O site, O(2) is bonded in a 4-coordinate geometry to one Ca(2), two equivalent Ca(1), one Fe(1), and one Fe(2) atom. In the fourth O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one Mn(1), and one Fe(2) atom. In the fifth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one Mn(1), and one Fe(2) atom.