Pr2S3 crystallizes in the tetragonal I-42d space group. There are three inequivalent Pr sites. In the first Pr site, Pr(1) is bonded to two equivalent S(2), two equivalent S(3), and four equivalent S(1) atoms to form a mixture of distorted face, corner, and edge-sharing PrS8 hexagonal bipyramids. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to two equivalent S(1), three equivalent S(2), and three equivalent S(3) atoms. In the third Pr site, Pr(3) is bonded to two equivalent S(1), two equivalent S(3), and four equivalent S(2) atoms to form a mixture of distorted face, corner, and edge-sharing PrS8 hexagonal bipyramids. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Pr(3), two equivalent Pr(1), and two equivalent Pr(2) atoms to form SPr5 trigonal bipyramids that share corners with five equivalent S(2)Pr6 octahedra, corners with four equivalent S(3)Pr5 square pyramids, corners with four equivalent S(1)Pr5 trigonal bipyramids, edges with three equivalent S(2)Pr6 octahedra, edges with four equivalent S(3)Pr5 square pyramids,  an edgeedge with one S(1)Pr5 trigonal bipyramid,  a faceface with one S(2)Pr6 octahedra, and  a faceface with one S(1)Pr5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 24-50°. In the second S site, S(2) is bonded to one Pr(1), two equivalent Pr(3), and three equivalent Pr(2) atoms to form distorted SPr6 octahedra that share corners with three equivalent S(2)Pr6 octahedra, corners with seven equivalent S(3)Pr5 square pyramids, corners with five equivalent S(1)Pr5 trigonal bipyramids, edges with two equivalent S(2)Pr6 octahedra,  an edgeedge with one S(3)Pr5 square pyramid, edges with three equivalent S(1)Pr5 trigonal bipyramids, faces with two equivalent S(2)Pr6 octahedra, faces with two equivalent S(3)Pr5 square pyramids, and  a faceface with one S(1)Pr5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 18-48°. In the third S site, S(3) is bonded to one Pr(1), one Pr(3), and three equivalent Pr(2) atoms to form distorted SPr5 square pyramids that share corners with seven equivalent S(2)Pr6 octahedra, corners with five equivalent S(3)Pr5 square pyramids, corners with four equivalent S(1)Pr5 trigonal bipyramids,  an edgeedge with one S(2)Pr6 octahedra, edges with four equivalent S(1)Pr5 trigonal bipyramids, faces with two equivalent S(2)Pr6 octahedra, and  a faceface with one S(3)Pr5 square pyramid. The corner-sharing octahedral tilt angles range from 12-55°.
Pr2S3 crystallizes in the tetragonal I-42d space group. There are three inequivalent Pr sites. In the first Pr site, Pr(1) is bonded to two equivalent S(2), two equivalent S(3), and four equivalent S(1) atoms to form a mixture of distorted face, corner, and edge-sharing PrS8 hexagonal bipyramids. Both Pr(1)-S(2) bond lengths are 3.15 Å. Both Pr(1)-S(3) bond lengths are 2.92 Å. There are two shorter (2.90 Å) and two longer (3.08 Å) Pr(1)-S(1) bond lengths. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to two equivalent S(1), three equivalent S(2), and three equivalent S(3) atoms. There is one shorter (2.85 Å) and one longer (3.08 Å) Pr(2)-S(1) bond length. There are a spread of Pr(2)-S(2) bond distances ranging from 2.89-3.27 Å. There are a spread of Pr(2)-S(3) bond distances ranging from 2.86-3.08 Å. In the third Pr site, Pr(3) is bonded to two equivalent S(1), two equivalent S(3), and four equivalent S(2) atoms to form a mixture of distorted face, corner, and edge-sharing PrS8 hexagonal bipyramids. Both Pr(3)-S(1) bond lengths are 2.88 Å. Both Pr(3)-S(3) bond lengths are 3.08 Å. There are two shorter (2.91 Å) and two longer (3.04 Å) Pr(3)-S(2) bond lengths. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Pr(3), two equivalent Pr(1), and two equivalent Pr(2) atoms to form SPr5 trigonal bipyramids that share corners with five equivalent S(2)Pr6 octahedra, corners with four equivalent S(3)Pr5 square pyramids, corners with four equivalent S(1)Pr5 trigonal bipyramids, edges with three equivalent S(2)Pr6 octahedra, edges with four equivalent S(3)Pr5 square pyramids,  an edgeedge with one S(1)Pr5 trigonal bipyramid,  a faceface with one S(2)Pr6 octahedra, and  a faceface with one S(1)Pr5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 24-50°. In the second S site, S(2) is bonded to one Pr(1), two equivalent Pr(3), and three equivalent Pr(2) atoms to form distorted SPr6 octahedra that share corners with three equivalent S(2)Pr6 octahedra, corners with seven equivalent S(3)Pr5 square pyramids, corners with five equivalent S(1)Pr5 trigonal bipyramids, edges with two equivalent S(2)Pr6 octahedra,  an edgeedge with one S(3)Pr5 square pyramid, edges with three equivalent S(1)Pr5 trigonal bipyramids, faces with two equivalent S(2)Pr6 octahedra, faces with two equivalent S(3)Pr5 square pyramids, and  a faceface with one S(1)Pr5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 18-48°. In the third S site, S(3) is bonded to one Pr(1), one Pr(3), and three equivalent Pr(2) atoms to form distorted SPr5 square pyramids that share corners with seven equivalent S(2)Pr6 octahedra, corners with five equivalent S(3)Pr5 square pyramids, corners with four equivalent S(1)Pr5 trigonal bipyramids,  an edgeedge with one S(2)Pr6 octahedra, edges with four equivalent S(1)Pr5 trigonal bipyramids, faces with two equivalent S(2)Pr6 octahedra, and  a faceface with one S(3)Pr5 square pyramid. The corner-sharing octahedral tilt angles range from 12-55°.