Mn3Fe3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 5-coordinate geometry to one N(1), one N(3), one N(4), and two equivalent N(2) atoms. In the second Mn site, Mn(2) is bonded to one N(3), one N(4), and two equivalent N(5) atoms to form MnN4 trigonal pyramids that share corners with two equivalent Fe(2)N4 tetrahedra and  an edgeedge with one Mn(2)N4 trigonal pyramid. In the third Mn site, Mn(3) is bonded in a distorted see-saw-like geometry to one N(1), one N(2), one N(3), and one N(5) atom. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a trigonal planar geometry to one N(1), one N(3), and one N(5) atom. In the second Fe site, Fe(2) is bonded to one N(1), one N(2), and two equivalent N(4) atoms to form distorted FeN4 tetrahedra that share corners with two equivalent Mn(2)N4 trigonal pyramids and  an edgeedge with one Fe(2)N4 tetrahedra. In the third Fe site, Fe(3) is bonded in a distorted rectangular see-saw-like geometry to one N(1), one N(2), one N(4), and one N(5) atom. There are five inequivalent N sites. In the first N site, N(1) is bonded in a 5-coordinate geometry to one Mn(1), one Mn(3), one Fe(1), one Fe(2), and one Fe(3) atom. In the second N site, N(2) is bonded to one Mn(3), two equivalent Mn(1), one Fe(2), and one Fe(3) atom to form distorted NMn3Fe2 trigonal bipyramids that share corners with two equivalent N(5)Mn3Fe2 trigonal bipyramids, corners with three equivalent N(4)Mn2Fe3 trigonal bipyramids,  an edgeedge with one N(4)Mn2Fe3 trigonal bipyramid, and  an edgeedge with one N(2)Mn3Fe2 trigonal bipyramid. In the third N site, N(3) is bonded in a see-saw-like geometry to one Mn(1), one Mn(2), one Mn(3), and one Fe(1) atom. In the fourth N site, N(4) is bonded to one Mn(1), one Mn(2), one Fe(3), and two equivalent Fe(2) atoms to form NMn2Fe3 trigonal bipyramids that share  a cornercorner with one N(5)Mn3Fe2 trigonal bipyramid, corners with three equivalent N(2)Mn3Fe2 trigonal bipyramids,  an edgeedge with one N(4)Mn2Fe3 trigonal bipyramid,  an edgeedge with one N(2)Mn3Fe2 trigonal bipyramid, and  an edgeedge with one N(5)Mn3Fe2 trigonal bipyramid. In the fifth N site, N(5) is bonded to one Mn(3), two equivalent Mn(2), one Fe(1), and one Fe(3) atom to form NMn3Fe2 trigonal bipyramids that share  a cornercorner with one N(4)Mn2Fe3 trigonal bipyramid, corners with two equivalent N(2)Mn3Fe2 trigonal bipyramids,  an edgeedge with one N(4)Mn2Fe3 trigonal bipyramid, and  an edgeedge with one N(5)Mn3Fe2 trigonal bipyramid.
Mn3Fe3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 5-coordinate geometry to one N(1), one N(3), one N(4), and two equivalent N(2) atoms. The Mn(1)-N(1) bond length is 2.23 Å. The Mn(1)-N(3) bond length is 1.94 Å. The Mn(1)-N(4) bond length is 1.89 Å. There is one shorter (1.89 Å) and one longer (2.08 Å) Mn(1)-N(2) bond length. In the second Mn site, Mn(2) is bonded to one N(3), one N(4), and two equivalent N(5) atoms to form MnN4 trigonal pyramids that share corners with two equivalent Fe(2)N4 tetrahedra and  an edgeedge with one Mn(2)N4 trigonal pyramid. The Mn(2)-N(3) bond length is 1.89 Å. The Mn(2)-N(4) bond length is 1.91 Å. There is one shorter (1.90 Å) and one longer (1.94 Å) Mn(2)-N(5) bond length. In the third Mn site, Mn(3) is bonded in a distorted see-saw-like geometry to one N(1), one N(2), one N(3), and one N(5) atom. The Mn(3)-N(1) bond length is 1.91 Å. The Mn(3)-N(2) bond length is 1.98 Å. The Mn(3)-N(3) bond length is 1.97 Å. The Mn(3)-N(5) bond length is 1.96 Å. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a trigonal planar geometry to one N(1), one N(3), and one N(5) atom. The Fe(1)-N(1) bond length is 1.82 Å. The Fe(1)-N(3) bond length is 1.84 Å. The Fe(1)-N(5) bond length is 1.82 Å. In the second Fe site, Fe(2) is bonded to one N(1), one N(2), and two equivalent N(4) atoms to form distorted FeN4 tetrahedra that share corners with two equivalent Mn(2)N4 trigonal pyramids and  an edgeedge with one Fe(2)N4 tetrahedra. The Fe(2)-N(1) bond length is 1.90 Å. The Fe(2)-N(2) bond length is 1.89 Å. There is one shorter (1.86 Å) and one longer (1.94 Å) Fe(2)-N(4) bond length. In the third Fe site, Fe(3) is bonded in a distorted rectangular see-saw-like geometry to one N(1), one N(2), one N(4), and one N(5) atom. The Fe(3)-N(1) bond length is 1.87 Å. The Fe(3)-N(2) bond length is 1.95 Å. The Fe(3)-N(4) bond length is 1.93 Å. The Fe(3)-N(5) bond length is 1.96 Å. There are five inequivalent N sites. In the first N site, N(1) is bonded in a 5-coordinate geometry to one Mn(1), one Mn(3), one Fe(1), one Fe(2), and one Fe(3) atom. In the second N site, N(2) is bonded to one Mn(3), two equivalent Mn(1), one Fe(2), and one Fe(3) atom to form distorted NMn3Fe2 trigonal bipyramids that share corners with two equivalent N(5)Mn3Fe2 trigonal bipyramids, corners with three equivalent N(4)Mn2Fe3 trigonal bipyramids,  an edgeedge with one N(4)Mn2Fe3 trigonal bipyramid, and  an edgeedge with one N(2)Mn3Fe2 trigonal bipyramid. In the third N site, N(3) is bonded in a see-saw-like geometry to one Mn(1), one Mn(2), one Mn(3), and one Fe(1) atom. In the fourth N site, N(4) is bonded to one Mn(1), one Mn(2), one Fe(3), and two equivalent Fe(2) atoms to form NMn2Fe3 trigonal bipyramids that share  a cornercorner with one N(5)Mn3Fe2 trigonal bipyramid, corners with three equivalent N(2)Mn3Fe2 trigonal bipyramids,  an edgeedge with one N(4)Mn2Fe3 trigonal bipyramid,  an edgeedge with one N(2)Mn3Fe2 trigonal bipyramid, and  an edgeedge with one N(5)Mn3Fe2 trigonal bipyramid. In the fifth N site, N(5) is bonded to one Mn(3), two equivalent Mn(2), one Fe(1), and one Fe(3) atom to form NMn3Fe2 trigonal bipyramids that share  a cornercorner with one N(4)Mn2Fe3 trigonal bipyramid, corners with two equivalent N(2)Mn3Fe2 trigonal bipyramids,  an edgeedge with one N(4)Mn2Fe3 trigonal bipyramid, and  an edgeedge with one N(5)Mn3Fe2 trigonal bipyramid.