Pr6Ti2S7O6 crystallizes in the monoclinic P2_1/m space group. There are six inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to two equivalent S(7), three equivalent S(6), one O(3), one O(4), and two equivalent O(2) atoms. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to two equivalent S(4), two equivalent S(7), three equivalent S(5), and one O(3) atom. In the third Pr site, Pr(3) is bonded in a 8-coordinate geometry to one S(7), two equivalent S(5), two equivalent S(6), one O(4), and two equivalent O(6) atoms. In the fourth Pr site, Pr(4) is bonded in a 9-coordinate geometry to two equivalent S(1), two equivalent S(4), three equivalent S(3), one O(1), and one O(3) atom. In the fifth Pr site, Pr(5) is bonded in a 7-coordinate geometry to two equivalent S(2), one O(2), one O(5), one O(6), and two equivalent O(4) atoms. In the sixth Pr site, Pr(6) is bonded in a 9-coordinate geometry to one S(1), two equivalent S(3), three equivalent S(2), one O(1), and two equivalent O(5) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 6-coordinate geometry to one S(1), one S(4), one S(7), one O(2), and two equivalent O(3) atoms. In the second Ti site, Ti(2) is bonded in a 4-coordinate geometry to one S(3), one S(4), one O(5), one O(6), and two equivalent O(1) atoms. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Pr(6), two equivalent Pr(4), and one Ti(1) atom. In the second S site, S(2) is bonded to two equivalent Pr(5) and three equivalent Pr(6) atoms to form SPr5 square pyramids that share corners with two equivalent O(2)Pr3Ti tetrahedra, corners with two equivalent O(5)Pr3Ti tetrahedra, corners with two equivalent O(4)Pr4 tetrahedra, edges with four equivalent S(2)Pr5 square pyramids,  an edgeedge with one O(4)Pr4 tetrahedra, and edges with three equivalent O(5)Pr3Ti tetrahedra. In the third S site, S(3) is bonded in a 6-coordinate geometry to two equivalent Pr(6), three equivalent Pr(4), and one Ti(2) atom. In the fourth S site, S(4) is bonded to two equivalent Pr(2), two equivalent Pr(4), one Ti(1), and one Ti(2) atom to form distorted SPr4Ti2 octahedra that share corners with two equivalent S(7)Pr5Ti pentagonal pyramids,  a cornercorner with one O(2)Pr3Ti tetrahedra,  a cornercorner with one O(5)Pr3Ti tetrahedra, corners with four equivalent S(5)Pr5 trigonal bipyramids, edges with two equivalent S(4)Pr4Ti2 octahedra,  an edgeedge with one S(5)Pr5 trigonal bipyramid, and  a faceface with one S(7)Pr5Ti pentagonal pyramid. In the fifth S site, S(5) is bonded to two equivalent Pr(3) and three equivalent Pr(2) atoms to form distorted SPr5 trigonal bipyramids that share corners with four equivalent S(4)Pr4Ti2 octahedra, corners with two equivalent S(7)Pr5Ti pentagonal pyramids, corners with two equivalent O(4)Pr4 tetrahedra, corners with two equivalent S(6)Pr5 trigonal bipyramids,  an edgeedge with one S(4)Pr4Ti2 octahedra, edges with three equivalent S(7)Pr5Ti pentagonal pyramids,  an edgeedge with one S(6)Pr5 trigonal bipyramid, and edges with four equivalent S(5)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 42-60°. In the sixth S site, S(6) is bonded to two equivalent Pr(3) and three equivalent Pr(1) atoms to form distorted SPr5 trigonal bipyramids that share corners with two equivalent S(7)Pr5Ti pentagonal pyramids,  a cornercorner with one O(4)Pr4 tetrahedra, corners with four equivalent O(2)Pr3Ti tetrahedra, corners with two equivalent S(5)Pr5 trigonal bipyramids, edges with three equivalent S(7)Pr5Ti pentagonal pyramids,  an edgeedge with one O(2)Pr3Ti tetrahedra, edges with two equivalent O(4)Pr4 tetrahedra,  an edgeedge with one S(5)Pr5 trigonal bipyramid, and edges with four equivalent S(6)Pr5 trigonal bipyramids. In the seventh S site, S(7) is bonded to one Pr(3), two equivalent Pr(1), two equivalent Pr(2), and one Ti(1) atom to form distorted SPr5Ti pentagonal pyramids that share corners with two equivalent S(4)Pr4Ti2 octahedra, corners with two equivalent O(2)Pr3Ti tetrahedra, corners with three equivalent O(4)Pr4 tetrahedra, corners with two equivalent S(5)Pr5 trigonal bipyramids, corners with two equivalent S(6)Pr5 trigonal bipyramids, edges with two equivalent S(7)Pr5Ti pentagonal pyramids, edges with three equivalent S(5)Pr5 trigonal bipyramids, edges with three equivalent S(6)Pr5 trigonal bipyramids,  a faceface with one S(4)Pr4Ti2 octahedra, and  a faceface with one O(2)Pr3Ti tetrahedra. The corner-sharing octahedral tilt angles are 45°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Pr(4), one Pr(6), and two equivalent Ti(2) atoms. In the second O site, O(2) is bonded to one Pr(5), two equivalent Pr(1), and one Ti(1) atom to form distorted OPr3Ti tetrahedra that share  a cornercorner with one S(4)Pr4Ti2 octahedra, corners with two equivalent S(7)Pr5Ti pentagonal pyramids, corners with two equivalent S(2)Pr5 square pyramids,  a cornercorner with one O(5)Pr3Ti tetrahedra, corners with two equivalent O(2)Pr3Ti tetrahedra, corners with four equivalent S(6)Pr5 trigonal bipyramids, edges with two equivalent O(4)Pr4 tetrahedra,  an edgeedge with one S(6)Pr5 trigonal bipyramid, and  a faceface with one S(7)Pr5Ti pentagonal pyramid. The corner-sharing octahedral tilt angles are 10°. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Pr(1), one Pr(2), one Pr(4), and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded to one Pr(1), one Pr(3), and two equivalent Pr(5) atoms to form OPr4 tetrahedra that share corners with three equivalent S(7)Pr5Ti pentagonal pyramids, corners with two equivalent S(2)Pr5 square pyramids, corners with two equivalent O(5)Pr3Ti tetrahedra, corners with two equivalent O(4)Pr4 tetrahedra,  a cornercorner with one S(6)Pr5 trigonal bipyramid, corners with two equivalent S(5)Pr5 trigonal bipyramids,  an edgeedge with one S(2)Pr5 square pyramid, edges with two equivalent O(2)Pr3Ti tetrahedra, and edges with two equivalent S(6)Pr5 trigonal bipyramids. In the fifth O site, O(5) is bonded to one Pr(5), two equivalent Pr(6), and one Ti(2) atom to form distorted OPr3Ti tetrahedra that share  a cornercorner with one S(4)Pr4Ti2 octahedra, corners with two equivalent S(2)Pr5 square pyramids,  a cornercorner with one O(2)Pr3Ti tetrahedra, corners with two equivalent O(5)Pr3Ti tetrahedra, corners with two equivalent O(4)Pr4 tetrahedra, and edges with three equivalent S(2)Pr5 square pyramids. The corner-sharing octahedral tilt angles are 15°. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Pr(5), two equivalent Pr(3), and one Ti(2) atom.
Pr6Ti2S7O6 crystallizes in the monoclinic P2_1/m space group. There are six inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to two equivalent S(7), three equivalent S(6), one O(3), one O(4), and two equivalent O(2) atoms. Both Pr(1)-S(7) bond lengths are 3.06 Å. All Pr(1)-S(6) bond lengths are 2.95 Å. The Pr(1)-O(3) bond length is 2.74 Å. The Pr(1)-O(4) bond length is 2.49 Å. Both Pr(1)-O(2) bond lengths are 2.49 Å. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to two equivalent S(4), two equivalent S(7), three equivalent S(5), and one O(3) atom. Both Pr(2)-S(4) bond lengths are 3.02 Å. Both Pr(2)-S(7) bond lengths are 2.85 Å. There is one shorter (2.91 Å) and two longer (2.93 Å) Pr(2)-S(5) bond lengths. The Pr(2)-O(3) bond length is 2.66 Å. In the third Pr site, Pr(3) is bonded in a 8-coordinate geometry to one S(7), two equivalent S(5), two equivalent S(6), one O(4), and two equivalent O(6) atoms. The Pr(3)-S(7) bond length is 3.22 Å. Both Pr(3)-S(5) bond lengths are 3.01 Å. Both Pr(3)-S(6) bond lengths are 2.90 Å. The Pr(3)-O(4) bond length is 2.39 Å. Both Pr(3)-O(6) bond lengths are 2.58 Å. In the fourth Pr site, Pr(4) is bonded in a 9-coordinate geometry to two equivalent S(1), two equivalent S(4), three equivalent S(3), one O(1), and one O(3) atom. Both Pr(4)-S(1) bond lengths are 2.93 Å. Both Pr(4)-S(4) bond lengths are 2.98 Å. There are two shorter (2.86 Å) and one longer (3.05 Å) Pr(4)-S(3) bond length. The Pr(4)-O(1) bond length is 2.70 Å. The Pr(4)-O(3) bond length is 3.21 Å. In the fifth Pr site, Pr(5) is bonded in a 7-coordinate geometry to two equivalent S(2), one O(2), one O(5), one O(6), and two equivalent O(4) atoms. Both Pr(5)-S(2) bond lengths are 2.98 Å. The Pr(5)-O(2) bond length is 2.44 Å. The Pr(5)-O(5) bond length is 2.48 Å. The Pr(5)-O(6) bond length is 2.55 Å. Both Pr(5)-O(4) bond lengths are 2.34 Å. In the sixth Pr site, Pr(6) is bonded in a 9-coordinate geometry to one S(1), two equivalent S(3), three equivalent S(2), one O(1), and two equivalent O(5) atoms. The Pr(6)-S(1) bond length is 3.10 Å. Both Pr(6)-S(3) bond lengths are 3.17 Å. There are two shorter (2.94 Å) and one longer (3.04 Å) Pr(6)-S(2) bond length. The Pr(6)-O(1) bond length is 2.76 Å. Both Pr(6)-O(5) bond lengths are 2.46 Å. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded in a 6-coordinate geometry to one S(1), one S(4), one S(7), one O(2), and two equivalent O(3) atoms. The Ti(1)-S(1) bond length is 2.29 Å. The Ti(1)-S(4) bond length is 2.64 Å. The Ti(1)-S(7) bond length is 2.73 Å. The Ti(1)-O(2) bond length is 1.81 Å. Both Ti(1)-O(3) bond lengths are 2.00 Å. In the second Ti site, Ti(2) is bonded in a 4-coordinate geometry to one S(3), one S(4), one O(5), one O(6), and two equivalent O(1) atoms. The Ti(2)-S(3) bond length is 2.85 Å. The Ti(2)-S(4) bond length is 2.61 Å. The Ti(2)-O(5) bond length is 1.86 Å. The Ti(2)-O(6) bond length is 1.82 Å. Both Ti(2)-O(1) bond lengths are 2.01 Å. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Pr(6), two equivalent Pr(4), and one Ti(1) atom. In the second S site, S(2) is bonded to two equivalent Pr(5) and three equivalent Pr(6) atoms to form SPr5 square pyramids that share corners with two equivalent O(2)Pr3Ti tetrahedra, corners with two equivalent O(5)Pr3Ti tetrahedra, corners with two equivalent O(4)Pr4 tetrahedra, edges with four equivalent S(2)Pr5 square pyramids,  an edgeedge with one O(4)Pr4 tetrahedra, and edges with three equivalent O(5)Pr3Ti tetrahedra. In the third S site, S(3) is bonded in a 6-coordinate geometry to two equivalent Pr(6), three equivalent Pr(4), and one Ti(2) atom. In the fourth S site, S(4) is bonded to two equivalent Pr(2), two equivalent Pr(4), one Ti(1), and one Ti(2) atom to form distorted SPr4Ti2 octahedra that share corners with two equivalent S(7)Pr5Ti pentagonal pyramids,  a cornercorner with one O(2)Pr3Ti tetrahedra,  a cornercorner with one O(5)Pr3Ti tetrahedra, corners with four equivalent S(5)Pr5 trigonal bipyramids, edges with two equivalent S(4)Pr4Ti2 octahedra,  an edgeedge with one S(5)Pr5 trigonal bipyramid, and  a faceface with one S(7)Pr5Ti pentagonal pyramid. In the fifth S site, S(5) is bonded to two equivalent Pr(3) and three equivalent Pr(2) atoms to form distorted SPr5 trigonal bipyramids that share corners with four equivalent S(4)Pr4Ti2 octahedra, corners with two equivalent S(7)Pr5Ti pentagonal pyramids, corners with two equivalent O(4)Pr4 tetrahedra, corners with two equivalent S(6)Pr5 trigonal bipyramids,  an edgeedge with one S(4)Pr4Ti2 octahedra, edges with three equivalent S(7)Pr5Ti pentagonal pyramids,  an edgeedge with one S(6)Pr5 trigonal bipyramid, and edges with four equivalent S(5)Pr5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 42-60°. In the sixth S site, S(6) is bonded to two equivalent Pr(3) and three equivalent Pr(1) atoms to form distorted SPr5 trigonal bipyramids that share corners with two equivalent S(7)Pr5Ti pentagonal pyramids,  a cornercorner with one O(4)Pr4 tetrahedra, corners with four equivalent O(2)Pr3Ti tetrahedra, corners with two equivalent S(5)Pr5 trigonal bipyramids, edges with three equivalent S(7)Pr5Ti pentagonal pyramids,  an edgeedge with one O(2)Pr3Ti tetrahedra, edges with two equivalent O(4)Pr4 tetrahedra,  an edgeedge with one S(5)Pr5 trigonal bipyramid, and edges with four equivalent S(6)Pr5 trigonal bipyramids. In the seventh S site, S(7) is bonded to one Pr(3), two equivalent Pr(1), two equivalent Pr(2), and one Ti(1) atom to form distorted SPr5Ti pentagonal pyramids that share corners with two equivalent S(4)Pr4Ti2 octahedra, corners with two equivalent O(2)Pr3Ti tetrahedra, corners with three equivalent O(4)Pr4 tetrahedra, corners with two equivalent S(5)Pr5 trigonal bipyramids, corners with two equivalent S(6)Pr5 trigonal bipyramids, edges with two equivalent S(7)Pr5Ti pentagonal pyramids, edges with three equivalent S(5)Pr5 trigonal bipyramids, edges with three equivalent S(6)Pr5 trigonal bipyramids,  a faceface with one S(4)Pr4Ti2 octahedra, and  a faceface with one O(2)Pr3Ti tetrahedra. The corner-sharing octahedral tilt angles are 45°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Pr(4), one Pr(6), and two equivalent Ti(2) atoms. In the second O site, O(2) is bonded to one Pr(5), two equivalent Pr(1), and one Ti(1) atom to form distorted OPr3Ti tetrahedra that share  a cornercorner with one S(4)Pr4Ti2 octahedra, corners with two equivalent S(7)Pr5Ti pentagonal pyramids, corners with two equivalent S(2)Pr5 square pyramids,  a cornercorner with one O(5)Pr3Ti tetrahedra, corners with two equivalent O(2)Pr3Ti tetrahedra, corners with four equivalent S(6)Pr5 trigonal bipyramids, edges with two equivalent O(4)Pr4 tetrahedra,  an edgeedge with one S(6)Pr5 trigonal bipyramid, and  a faceface with one S(7)Pr5Ti pentagonal pyramid. The corner-sharing octahedral tilt angles are 10°. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Pr(1), one Pr(2), one Pr(4), and two equivalent Ti(1) atoms. In the fourth O site, O(4) is bonded to one Pr(1), one Pr(3), and two equivalent Pr(5) atoms to form OPr4 tetrahedra that share corners with three equivalent S(7)Pr5Ti pentagonal pyramids, corners with two equivalent S(2)Pr5 square pyramids, corners with two equivalent O(5)Pr3Ti tetrahedra, corners with two equivalent O(4)Pr4 tetrahedra,  a cornercorner with one S(6)Pr5 trigonal bipyramid, corners with two equivalent S(5)Pr5 trigonal bipyramids,  an edgeedge with one S(2)Pr5 square pyramid, edges with two equivalent O(2)Pr3Ti tetrahedra, and edges with two equivalent S(6)Pr5 trigonal bipyramids. In the fifth O site, O(5) is bonded to one Pr(5), two equivalent Pr(6), and one Ti(2) atom to form distorted OPr3Ti tetrahedra that share  a cornercorner with one S(4)Pr4Ti2 octahedra, corners with two equivalent S(2)Pr5 square pyramids,  a cornercorner with one O(2)Pr3Ti tetrahedra, corners with two equivalent O(5)Pr3Ti tetrahedra, corners with two equivalent O(4)Pr4 tetrahedra, and edges with three equivalent S(2)Pr5 square pyramids. The corner-sharing octahedral tilt angles are 15°. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Pr(5), two equivalent Pr(3), and one Ti(2) atom.