CsPr(SO4)2 crystallizes in the orthorhombic Pnna space group. Cs(1) is bonded in a 14-coordinate geometry to two equivalent O(1), four equivalent O(2), four equivalent O(3), and four equivalent O(4) atoms. Pr(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted PrO8 hexagonal bipyramids that share corners with four equivalent S(1)O4 tetrahedra and edges with two equivalent S(1)O4 tetrahedra. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share corners with two equivalent Pr(1)O8 hexagonal bipyramids and  an edgeedge with one Pr(1)O8 hexagonal bipyramid. There are four inequivalent O sites. In the first O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Cs(1), one Pr(1), and one S(1) atom. In the second O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Cs(1), one Pr(1), and one S(1) atom. In the third O site, O(1) is bonded in a distorted single-bond geometry to one Cs(1), one Pr(1), and one S(1) atom. In the fourth O site, O(2) is bonded in a 1-coordinate geometry to two equivalent Cs(1), one Pr(1), and one S(1) atom.
CsPr(SO4)2 crystallizes in the orthorhombic Pnna space group. Cs(1) is bonded in a 14-coordinate geometry to two equivalent O(1), four equivalent O(2), four equivalent O(3), and four equivalent O(4) atoms. Both Cs(1)-O(1) bond lengths are 3.43 Å. There are two shorter (3.31 Å) and two longer (3.52 Å) Cs(1)-O(2) bond lengths. There are two shorter (3.21 Å) and two longer (3.31 Å) Cs(1)-O(3) bond lengths. There are two shorter (3.39 Å) and two longer (3.68 Å) Cs(1)-O(4) bond lengths. Pr(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted PrO8 hexagonal bipyramids that share corners with four equivalent S(1)O4 tetrahedra and edges with two equivalent S(1)O4 tetrahedra. Both Pr(1)-O(1) bond lengths are 2.54 Å. Both Pr(1)-O(2) bond lengths are 2.51 Å. Both Pr(1)-O(3) bond lengths are 2.56 Å. Both Pr(1)-O(4) bond lengths are 2.50 Å. S(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SO4 tetrahedra that share corners with two equivalent Pr(1)O8 hexagonal bipyramids and  an edgeedge with one Pr(1)O8 hexagonal bipyramid. The S(1)-O(1) bond length is 1.50 Å. The S(1)-O(2) bond length is 1.49 Å. The S(1)-O(3) bond length is 1.50 Å. The S(1)-O(4) bond length is 1.49 Å. There are four inequivalent O sites. In the first O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Cs(1), one Pr(1), and one S(1) atom. In the second O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Cs(1), one Pr(1), and one S(1) atom. In the third O site, O(1) is bonded in a distorted single-bond geometry to one Cs(1), one Pr(1), and one S(1) atom. In the fourth O site, O(2) is bonded in a 1-coordinate geometry to two equivalent Cs(1), one Pr(1), and one S(1) atom.