Ce3Ta(O2Cl3)2 crystallizes in the hexagonal P6_3/m space group. Ce(1) is bonded in a 2-coordinate geometry to two equivalent O(1), three equivalent Cl(2), and four equivalent Cl(1) atoms. Ta(1) is bonded to two equivalent O(2) and three equivalent O(1) atoms to form corner-sharing TaO5 trigonal bipyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Ce(1) and one Ta(1) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent Ta(1) atoms. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to four equivalent Ce(1) atoms to form a mixture of distorted corner and edge-sharing ClCe4 tetrahedra. In the second Cl site, Cl(2) is bonded in a trigonal non-coplanar geometry to three equivalent Ce(1) atoms.
Ce3Ta(O2Cl3)2 crystallizes in the hexagonal P6_3/m space group. Ce(1) is bonded in a 2-coordinate geometry to two equivalent O(1), three equivalent Cl(2), and four equivalent Cl(1) atoms. Both Ce(1)-O(1) bond lengths are 2.38 Å. There are two shorter (2.89 Å) and one longer (3.10 Å) Ce(1)-Cl(2) bond length. There are a spread of Ce(1)-Cl(1) bond distances ranging from 3.00-3.35 Å. Ta(1) is bonded to two equivalent O(2) and three equivalent O(1) atoms to form corner-sharing TaO5 trigonal bipyramids. Both Ta(1)-O(2) bond lengths are 1.98 Å. All Ta(1)-O(1) bond lengths are 1.91 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to two equivalent Ce(1) and one Ta(1) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent Ta(1) atoms. There are two inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to four equivalent Ce(1) atoms to form a mixture of distorted corner and edge-sharing ClCe4 tetrahedra. In the second Cl site, Cl(2) is bonded in a trigonal non-coplanar geometry to three equivalent Ce(1) atoms.