PrSO crystallizes in the monoclinic Cm space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 4-coordinate geometry to one S(1), one S(2), one S(3), one S(4), two equivalent O(1), and two equivalent O(2) atoms. In the second Pr site, Pr(2) is bonded in a 4-coordinate geometry to one S(1), one S(2), one S(3), one S(4), two equivalent O(1), and two equivalent O(2) atoms. There are four inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one S(4) atom to form distorted SPr4S trigonal bipyramids that share corners with four equivalent O(1)Pr4 tetrahedra, corners with eight equivalent O(2)Pr4 tetrahedra, edges with two equivalent O(1)Pr4 tetrahedra, edges with two equivalent S(2)Pr4S trigonal bipyramids, edges with two equivalent S(3)Pr4S trigonal bipyramids, and edges with two equivalent S(4)Pr4S trigonal bipyramids. In the second S site, S(2) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one S(3) atom to form distorted SPr4S trigonal bipyramids that share corners with four equivalent O(1)Pr4 tetrahedra, corners with eight equivalent O(2)Pr4 tetrahedra, edges with two equivalent O(1)Pr4 tetrahedra, edges with two equivalent S(1)Pr4S trigonal bipyramids, edges with two equivalent S(3)Pr4S trigonal bipyramids, and edges with two equivalent S(4)Pr4S trigonal bipyramids. In the third S site, S(3) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one S(2) atom to form distorted SPr4S trigonal bipyramids that share corners with four equivalent O(2)Pr4 tetrahedra, corners with eight equivalent O(1)Pr4 tetrahedra, edges with two equivalent O(2)Pr4 tetrahedra, edges with two equivalent S(1)Pr4S trigonal bipyramids, edges with two equivalent S(2)Pr4S trigonal bipyramids, and edges with two equivalent S(4)Pr4S trigonal bipyramids. In the fourth S site, S(4) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one S(1) atom to form distorted SPr4S trigonal bipyramids that share corners with four equivalent O(2)Pr4 tetrahedra, corners with eight equivalent O(1)Pr4 tetrahedra, edges with two equivalent O(2)Pr4 tetrahedra, edges with two equivalent S(1)Pr4S trigonal bipyramids, edges with two equivalent S(2)Pr4S trigonal bipyramids, and edges with two equivalent S(3)Pr4S trigonal bipyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Pr(1) and two equivalent Pr(2) atoms to form OPr4 tetrahedra that share corners with four equivalent O(2)Pr4 tetrahedra, corners with two equivalent S(1)Pr4S trigonal bipyramids, corners with two equivalent S(2)Pr4S trigonal bipyramids, corners with four equivalent S(3)Pr4S trigonal bipyramids, corners with four equivalent S(4)Pr4S trigonal bipyramids, edges with two equivalent O(1)Pr4 tetrahedra, edges with two equivalent O(2)Pr4 tetrahedra,  an edgeedge with one S(1)Pr4S trigonal bipyramid, and  an edgeedge with one S(2)Pr4S trigonal bipyramid. In the second O site, O(2) is bonded to two equivalent Pr(1) and two equivalent Pr(2) atoms to form OPr4 tetrahedra that share corners with four equivalent O(1)Pr4 tetrahedra, corners with two equivalent S(3)Pr4S trigonal bipyramids, corners with two equivalent S(4)Pr4S trigonal bipyramids, corners with four equivalent S(1)Pr4S trigonal bipyramids, corners with four equivalent S(2)Pr4S trigonal bipyramids, edges with two equivalent O(1)Pr4 tetrahedra, edges with two equivalent O(2)Pr4 tetrahedra,  an edgeedge with one S(3)Pr4S trigonal bipyramid, and  an edgeedge with one S(4)Pr4S trigonal bipyramid.
PrSO crystallizes in the monoclinic Cm space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 4-coordinate geometry to one S(1), one S(2), one S(3), one S(4), two equivalent O(1), and two equivalent O(2) atoms. The Pr(1)-S(1) bond length is 3.15 Å. The Pr(1)-S(2) bond length is 3.14 Å. The Pr(1)-S(3) bond length is 3.14 Å. The Pr(1)-S(4) bond length is 3.14 Å. There is one shorter (2.36 Å) and one longer (2.41 Å) Pr(1)-O(1) bond length. There is one shorter (2.37 Å) and one longer (2.40 Å) Pr(1)-O(2) bond length. In the second Pr site, Pr(2) is bonded in a 4-coordinate geometry to one S(1), one S(2), one S(3), one S(4), two equivalent O(1), and two equivalent O(2) atoms. The Pr(2)-S(1) bond length is 3.14 Å. The Pr(2)-S(2) bond length is 3.15 Å. The Pr(2)-S(3) bond length is 3.14 Å. The Pr(2)-S(4) bond length is 3.14 Å. There is one shorter (2.36 Å) and one longer (2.41 Å) Pr(2)-O(1) bond length. There is one shorter (2.36 Å) and one longer (2.40 Å) Pr(2)-O(2) bond length. There are four inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one S(4) atom to form distorted SPr4S trigonal bipyramids that share corners with four equivalent O(1)Pr4 tetrahedra, corners with eight equivalent O(2)Pr4 tetrahedra, edges with two equivalent O(1)Pr4 tetrahedra, edges with two equivalent S(2)Pr4S trigonal bipyramids, edges with two equivalent S(3)Pr4S trigonal bipyramids, and edges with two equivalent S(4)Pr4S trigonal bipyramids. The S(1)-S(4) bond length is 2.09 Å. In the second S site, S(2) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one S(3) atom to form distorted SPr4S trigonal bipyramids that share corners with four equivalent O(1)Pr4 tetrahedra, corners with eight equivalent O(2)Pr4 tetrahedra, edges with two equivalent O(1)Pr4 tetrahedra, edges with two equivalent S(1)Pr4S trigonal bipyramids, edges with two equivalent S(3)Pr4S trigonal bipyramids, and edges with two equivalent S(4)Pr4S trigonal bipyramids. The S(2)-S(3) bond length is 2.09 Å. In the third S site, S(3) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one S(2) atom to form distorted SPr4S trigonal bipyramids that share corners with four equivalent O(2)Pr4 tetrahedra, corners with eight equivalent O(1)Pr4 tetrahedra, edges with two equivalent O(2)Pr4 tetrahedra, edges with two equivalent S(1)Pr4S trigonal bipyramids, edges with two equivalent S(2)Pr4S trigonal bipyramids, and edges with two equivalent S(4)Pr4S trigonal bipyramids. In the fourth S site, S(4) is bonded to two equivalent Pr(1), two equivalent Pr(2), and one S(1) atom to form distorted SPr4S trigonal bipyramids that share corners with four equivalent O(2)Pr4 tetrahedra, corners with eight equivalent O(1)Pr4 tetrahedra, edges with two equivalent O(2)Pr4 tetrahedra, edges with two equivalent S(1)Pr4S trigonal bipyramids, edges with two equivalent S(2)Pr4S trigonal bipyramids, and edges with two equivalent S(3)Pr4S trigonal bipyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Pr(1) and two equivalent Pr(2) atoms to form OPr4 tetrahedra that share corners with four equivalent O(2)Pr4 tetrahedra, corners with two equivalent S(1)Pr4S trigonal bipyramids, corners with two equivalent S(2)Pr4S trigonal bipyramids, corners with four equivalent S(3)Pr4S trigonal bipyramids, corners with four equivalent S(4)Pr4S trigonal bipyramids, edges with two equivalent O(1)Pr4 tetrahedra, edges with two equivalent O(2)Pr4 tetrahedra,  an edgeedge with one S(1)Pr4S trigonal bipyramid, and  an edgeedge with one S(2)Pr4S trigonal bipyramid. In the second O site, O(2) is bonded to two equivalent Pr(1) and two equivalent Pr(2) atoms to form OPr4 tetrahedra that share corners with four equivalent O(1)Pr4 tetrahedra, corners with two equivalent S(3)Pr4S trigonal bipyramids, corners with two equivalent S(4)Pr4S trigonal bipyramids, corners with four equivalent S(1)Pr4S trigonal bipyramids, corners with four equivalent S(2)Pr4S trigonal bipyramids, edges with two equivalent O(1)Pr4 tetrahedra, edges with two equivalent O(2)Pr4 tetrahedra,  an edgeedge with one S(3)Pr4S trigonal bipyramid, and  an edgeedge with one S(4)Pr4S trigonal bipyramid.