Ce8Fe8As8O7F crystallizes in the orthorhombic F222 space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), one O(1), one O(2), one O(3), and one F(1) atom. In the second Ce site, Ce(2) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), one O(1), one O(2), one O(3), and one O(4) atom. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. In the second Fe site, Fe(3) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. In the third Fe site, Fe(2) is bonded to four equivalent As(1) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. In the fourth Fe site, Fe(4) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. In the fifth Fe site, Fe(5) is bonded in a 4-coordinate geometry to four equivalent As(2) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to two equivalent Ce(1), two equivalent Ce(2), one Fe(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the second As site, As(2) is bonded in a 8-coordinate geometry to two equivalent Ce(1), two equivalent Ce(2), one Fe(1), one Fe(3), one Fe(4), and one Fe(5) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form OCe4 tetrahedra that share corners with four equivalent O(2)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one F(1)Ce4 tetrahedra, and edges with two equivalent O(3)Ce4 tetrahedra. In the second O site, O(2) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form OCe4 tetrahedra that share corners with four equivalent O(1)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one F(1)Ce4 tetrahedra, and edges with two equivalent O(3)Ce4 tetrahedra. In the third O site, O(3) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form OCe4 tetrahedra that share corners with two equivalent O(4)Ce4 tetrahedra, corners with two equivalent F(1)Ce4 tetrahedra, edges with two equivalent O(1)Ce4 tetrahedra, and edges with two equivalent O(2)Ce4 tetrahedra. In the fourth O site, O(4) is bonded to four equivalent Ce(2) atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra. F(1) is bonded to four equivalent Ce(1) atoms to form FCe4 tetrahedra that share corners with four equivalent O(3)Ce4 tetrahedra, edges with two equivalent O(1)Ce4 tetrahedra, and edges with two equivalent O(2)Ce4 tetrahedra.
Ce8Fe8As8O7F crystallizes in the orthorhombic F222 space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), one O(1), one O(2), one O(3), and one F(1) atom. Both Ce(1)-As(1) bond lengths are 3.13 Å. There is one shorter (3.21 Å) and one longer (3.22 Å) Ce(1)-As(2) bond length. The Ce(1)-O(1) bond length is 2.37 Å. The Ce(1)-O(2) bond length is 2.37 Å. The Ce(1)-O(3) bond length is 2.30 Å. The Ce(1)-F(1) bond length is 2.46 Å. In the second Ce site, Ce(2) is bonded in a 4-coordinate geometry to two equivalent As(1), two equivalent As(2), one O(1), one O(2), one O(3), and one O(4) atom. There is one shorter (3.21 Å) and one longer (3.22 Å) Ce(2)-As(1) bond length. There is one shorter (3.20 Å) and one longer (3.21 Å) Ce(2)-As(2) bond length. The Ce(2)-O(1) bond length is 2.37 Å. The Ce(2)-O(2) bond length is 2.36 Å. The Ce(2)-O(3) bond length is 2.36 Å. The Ce(2)-O(4) bond length is 2.34 Å. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. Both Fe(1)-As(1) bond lengths are 2.59 Å. Both Fe(1)-As(2) bond lengths are 2.60 Å. In the second Fe site, Fe(3) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. Both Fe(3)-As(1) bond lengths are 2.61 Å. Both Fe(3)-As(2) bond lengths are 2.59 Å. In the third Fe site, Fe(2) is bonded to four equivalent As(1) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. All Fe(2)-As(1) bond lengths are 2.59 Å. In the fourth Fe site, Fe(4) is bonded to two equivalent As(1) and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. Both Fe(4)-As(1) bond lengths are 2.61 Å. Both Fe(4)-As(2) bond lengths are 2.60 Å. In the fifth Fe site, Fe(5) is bonded in a 4-coordinate geometry to four equivalent As(2) atoms. All Fe(5)-As(2) bond lengths are 2.62 Å. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to two equivalent Ce(1), two equivalent Ce(2), one Fe(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the second As site, As(2) is bonded in a 8-coordinate geometry to two equivalent Ce(1), two equivalent Ce(2), one Fe(1), one Fe(3), one Fe(4), and one Fe(5) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form OCe4 tetrahedra that share corners with four equivalent O(2)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one F(1)Ce4 tetrahedra, and edges with two equivalent O(3)Ce4 tetrahedra. In the second O site, O(2) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form OCe4 tetrahedra that share corners with four equivalent O(1)Ce4 tetrahedra,  an edgeedge with one O(4)Ce4 tetrahedra,  an edgeedge with one F(1)Ce4 tetrahedra, and edges with two equivalent O(3)Ce4 tetrahedra. In the third O site, O(3) is bonded to two equivalent Ce(1) and two equivalent Ce(2) atoms to form OCe4 tetrahedra that share corners with two equivalent O(4)Ce4 tetrahedra, corners with two equivalent F(1)Ce4 tetrahedra, edges with two equivalent O(1)Ce4 tetrahedra, and edges with two equivalent O(2)Ce4 tetrahedra. In the fourth O site, O(4) is bonded to four equivalent Ce(2) atoms to form a mixture of corner and edge-sharing OCe4 tetrahedra. F(1) is bonded to four equivalent Ce(1) atoms to form FCe4 tetrahedra that share corners with four equivalent O(3)Ce4 tetrahedra, edges with two equivalent O(1)Ce4 tetrahedra, and edges with two equivalent O(2)Ce4 tetrahedra.