Ca2Fe2O5 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second Ca site, Ca(2) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. Fe(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing FeO5 square pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded to one Ca(1), one Ca(2), and two equivalent Fe(1) atoms to form a mixture of distorted corner and edge-sharing OCa2Fe2 trigonal pyramids. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Ca(2), and two equivalent Fe(1) atoms.
Ca2Fe2O5 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. The Ca(1)-O(1) bond length is 2.27 Å. Both Ca(1)-O(2) bond lengths are 2.40 Å. Both Ca(1)-O(3) bond lengths are 2.29 Å. In the second Ca site, Ca(2) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. The Ca(2)-O(1) bond length is 2.47 Å. Both Ca(2)-O(2) bond lengths are 2.35 Å. Both Ca(2)-O(3) bond lengths are 2.38 Å. Fe(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing FeO5 square pyramids. The Fe(1)-O(1) bond length is 1.92 Å. There is one shorter (2.00 Å) and one longer (2.04 Å) Fe(1)-O(2) bond length. There is one shorter (1.99 Å) and one longer (2.07 Å) Fe(1)-O(3) bond length. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded to one Ca(1), one Ca(2), and two equivalent Fe(1) atoms to form a mixture of distorted corner and edge-sharing OCa2Fe2 trigonal pyramids. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Ca(2), and two equivalent Fe(1) atoms.