CdBi3O7 crystallizes in the monoclinic Cm space group. Cd(1) is bonded to one O(5) and three equivalent O(3) atoms to form CdO4 tetrahedra that share corners with three equivalent Bi(1)O7 hexagonal pyramids and corners with six equivalent Cd(1)O4 tetrahedra. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(6), three equivalent O(2), and three equivalent O(5) atoms to form distorted BiO7 hexagonal pyramids that share corners with three equivalent Cd(1)O4 tetrahedra and edges with six equivalent Bi(1)O7 hexagonal pyramids. In the second Bi site, Bi(2) is bonded in a distorted body-centered cubic geometry to one O(2), one O(7), three equivalent O(4), and three equivalent O(6) atoms. In the third Bi site, Bi(3) is bonded in a 5-coordinate geometry to one O(3), one O(7), and three equivalent O(1) atoms. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to three equivalent Bi(3) atoms. In the second O site, O(2) is bonded to one Bi(2) and three equivalent Bi(1) atoms to form OBi4 tetrahedra that share corners with three equivalent O(5)CdBi3 tetrahedra, corners with six equivalent O(2)Bi4 tetrahedra, edges with three equivalent O(6)Bi4 tetrahedra, and edges with three equivalent O(5)CdBi3 tetrahedra. In the third O site, O(3) is bonded to three equivalent Cd(1) and one Bi(3) atom to form OCd3Bi tetrahedra that share corners with three equivalent O(5)CdBi3 tetrahedra and corners with six equivalent O(3)Cd3Bi tetrahedra. In the fourth O site, O(4) is bonded in a trigonal planar geometry to three equivalent Bi(2) atoms. In the fifth O site, O(5) is bonded to one Cd(1) and three equivalent Bi(1) atoms to form OCdBi3 tetrahedra that share corners with three equivalent O(2)Bi4 tetrahedra, corners with three equivalent O(6)Bi4 tetrahedra, corners with three equivalent O(3)Cd3Bi tetrahedra, corners with six equivalent O(5)CdBi3 tetrahedra, and edges with three equivalent O(2)Bi4 tetrahedra. In the sixth O site, O(6) is bonded to one Bi(1) and three equivalent Bi(2) atoms to form OBi4 tetrahedra that share corners with three equivalent O(5)CdBi3 tetrahedra, corners with six equivalent O(6)Bi4 tetrahedra, and edges with three equivalent O(2)Bi4 tetrahedra. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Bi(2) and one Bi(3) atom.
CdBi3O7 crystallizes in the monoclinic Cm space group. Cd(1) is bonded to one O(5) and three equivalent O(3) atoms to form CdO4 tetrahedra that share corners with three equivalent Bi(1)O7 hexagonal pyramids and corners with six equivalent Cd(1)O4 tetrahedra. The Cd(1)-O(5) bond length is 2.26 Å. There are two shorter (2.27 Å) and one longer (2.30 Å) Cd(1)-O(3) bond length. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(6), three equivalent O(2), and three equivalent O(5) atoms to form distorted BiO7 hexagonal pyramids that share corners with three equivalent Cd(1)O4 tetrahedra and edges with six equivalent Bi(1)O7 hexagonal pyramids. The Bi(1)-O(6) bond length is 2.29 Å. There is one shorter (2.34 Å) and two longer (2.39 Å) Bi(1)-O(2) bond lengths. There is one shorter (2.40 Å) and two longer (2.47 Å) Bi(1)-O(5) bond lengths. In the second Bi site, Bi(2) is bonded in a distorted body-centered cubic geometry to one O(2), one O(7), three equivalent O(4), and three equivalent O(6) atoms. The Bi(2)-O(2) bond length is 2.30 Å. The Bi(2)-O(7) bond length is 2.13 Å. There is one shorter (2.20 Å) and two longer (2.28 Å) Bi(2)-O(4) bond lengths. There is one shorter (2.27 Å) and two longer (2.42 Å) Bi(2)-O(6) bond lengths. In the third Bi site, Bi(3) is bonded in a 5-coordinate geometry to one O(3), one O(7), and three equivalent O(1) atoms. The Bi(3)-O(3) bond length is 2.34 Å. The Bi(3)-O(7) bond length is 2.41 Å. There are two shorter (2.33 Å) and one longer (2.34 Å) Bi(3)-O(1) bond length. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to three equivalent Bi(3) atoms. In the second O site, O(2) is bonded to one Bi(2) and three equivalent Bi(1) atoms to form OBi4 tetrahedra that share corners with three equivalent O(5)CdBi3 tetrahedra, corners with six equivalent O(2)Bi4 tetrahedra, edges with three equivalent O(6)Bi4 tetrahedra, and edges with three equivalent O(5)CdBi3 tetrahedra. In the third O site, O(3) is bonded to three equivalent Cd(1) and one Bi(3) atom to form OCd3Bi tetrahedra that share corners with three equivalent O(5)CdBi3 tetrahedra and corners with six equivalent O(3)Cd3Bi tetrahedra. In the fourth O site, O(4) is bonded in a trigonal planar geometry to three equivalent Bi(2) atoms. In the fifth O site, O(5) is bonded to one Cd(1) and three equivalent Bi(1) atoms to form OCdBi3 tetrahedra that share corners with three equivalent O(2)Bi4 tetrahedra, corners with three equivalent O(6)Bi4 tetrahedra, corners with three equivalent O(3)Cd3Bi tetrahedra, corners with six equivalent O(5)CdBi3 tetrahedra, and edges with three equivalent O(2)Bi4 tetrahedra. In the sixth O site, O(6) is bonded to one Bi(1) and three equivalent Bi(2) atoms to form OBi4 tetrahedra that share corners with three equivalent O(5)CdBi3 tetrahedra, corners with six equivalent O(6)Bi4 tetrahedra, and edges with three equivalent O(2)Bi4 tetrahedra. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Bi(2) and one Bi(3) atom.