Sr4Fe4O13 crystallizes in the orthorhombic Iba2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(2), one O(5), two equivalent O(3), two equivalent O(4), and three equivalent O(1) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(1), one O(6), two equivalent O(3), two equivalent O(4), and three equivalent O(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), two equivalent O(5), and two equivalent O(7) atoms to form a mixture of distorted edge and corner-sharing FeO5 trigonal bipyramids. In the second Fe site, Fe(2) is bonded to one O(2), one O(5), and three equivalent O(6) atoms to form a mixture of edge and corner-sharing FeO5 trigonal bipyramids. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Sr(2), three equivalent Sr(1), and one Fe(1) atom. In the second O site, O(2) is bonded to one Sr(1), three equivalent Sr(2), and one Fe(2) atom to form distorted OSr4Fe trigonal bipyramids that share corners with two equivalent O(2)Sr4Fe trigonal bipyramids, edges with two equivalent O(2)Sr4Fe trigonal bipyramids, and  an edgeedge with one O(5)SrFe3 trigonal pyramid. In the third O site, O(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one O(4) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one O(3) atom. In the fifth O site, O(5) is bonded to one Sr(1), one Fe(2), and two equivalent Fe(1) atoms to form distorted OSrFe3 trigonal pyramids that share corners with two equivalent O(7)Fe4 trigonal pyramids, corners with two equivalent O(5)SrFe3 trigonal pyramids,  an edgeedge with one O(2)Sr4Fe trigonal bipyramid, and  an edgeedge with one O(7)Fe4 trigonal pyramid. In the sixth O site, O(6) is bonded in a distorted see-saw-like geometry to one Sr(2) and three equivalent Fe(2) atoms. In the seventh O site, O(7) is bonded to four equivalent Fe(1) atoms to form distorted OFe4 trigonal pyramids that share corners with four equivalent O(5)SrFe3 trigonal pyramids, edges with two equivalent O(7)Fe4 trigonal pyramids, and edges with two equivalent O(5)SrFe3 trigonal pyramids.
Sr4Fe4O13 crystallizes in the orthorhombic Iba2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(2), one O(5), two equivalent O(3), two equivalent O(4), and three equivalent O(1) atoms. The Sr(1)-O(2) bond length is 2.68 Å. The Sr(1)-O(5) bond length is 2.65 Å. There is one shorter (2.61 Å) and one longer (3.05 Å) Sr(1)-O(3) bond length. There is one shorter (2.60 Å) and one longer (3.20 Å) Sr(1)-O(4) bond length. There are a spread of Sr(1)-O(1) bond distances ranging from 2.61-2.69 Å. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(1), one O(6), two equivalent O(3), two equivalent O(4), and three equivalent O(2) atoms. The Sr(2)-O(1) bond length is 2.76 Å. The Sr(2)-O(6) bond length is 2.67 Å. There is one shorter (2.60 Å) and one longer (3.01 Å) Sr(2)-O(3) bond length. There is one shorter (2.59 Å) and one longer (2.87 Å) Sr(2)-O(4) bond length. There are two shorter (2.58 Å) and one longer (2.63 Å) Sr(2)-O(2) bond length. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), two equivalent O(5), and two equivalent O(7) atoms to form a mixture of distorted edge and corner-sharing FeO5 trigonal bipyramids. The Fe(1)-O(1) bond length is 1.87 Å. There is one shorter (1.98 Å) and one longer (2.04 Å) Fe(1)-O(5) bond length. There is one shorter (1.96 Å) and one longer (2.09 Å) Fe(1)-O(7) bond length. In the second Fe site, Fe(2) is bonded to one O(2), one O(5), and three equivalent O(6) atoms to form a mixture of edge and corner-sharing FeO5 trigonal bipyramids. The Fe(2)-O(2) bond length is 1.88 Å. The Fe(2)-O(5) bond length is 1.94 Å. There are a spread of Fe(2)-O(6) bond distances ranging from 2.01-2.11 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Sr(2), three equivalent Sr(1), and one Fe(1) atom. In the second O site, O(2) is bonded to one Sr(1), three equivalent Sr(2), and one Fe(2) atom to form distorted OSr4Fe trigonal bipyramids that share corners with two equivalent O(2)Sr4Fe trigonal bipyramids, edges with two equivalent O(2)Sr4Fe trigonal bipyramids, and  an edgeedge with one O(5)SrFe3 trigonal pyramid. In the third O site, O(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one O(4) atom. The O(3)-O(4) bond length is 1.39 Å. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one O(3) atom. In the fifth O site, O(5) is bonded to one Sr(1), one Fe(2), and two equivalent Fe(1) atoms to form distorted OSrFe3 trigonal pyramids that share corners with two equivalent O(7)Fe4 trigonal pyramids, corners with two equivalent O(5)SrFe3 trigonal pyramids,  an edgeedge with one O(2)Sr4Fe trigonal bipyramid, and  an edgeedge with one O(7)Fe4 trigonal pyramid. In the sixth O site, O(6) is bonded in a distorted see-saw-like geometry to one Sr(2) and three equivalent Fe(2) atoms. In the seventh O site, O(7) is bonded to four equivalent Fe(1) atoms to form distorted OFe4 trigonal pyramids that share corners with four equivalent O(5)SrFe3 trigonal pyramids, edges with two equivalent O(7)Fe4 trigonal pyramids, and edges with two equivalent O(5)SrFe3 trigonal pyramids.