Tm2S3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 8-coordinate geometry to two equivalent S(1), three equivalent S(2), and three equivalent S(3) atoms. In the second Tm site, Tm(2) is bonded to two equivalent S(2), two equivalent S(3), and three equivalent S(1) atoms to form a mixture of distorted edge and corner-sharing TmS7 pentagonal bipyramids. There are three inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Tm(1) and three equivalent Tm(2) atoms to form a mixture of edge and corner-sharing STm5 square pyramids. In the second S site, S(2) is bonded in a 5-coordinate geometry to two equivalent Tm(2) and three equivalent Tm(1) atoms. In the third S site, S(3) is bonded to two equivalent Tm(2) and three equivalent Tm(1) atoms to form a mixture of distorted edge and corner-sharing STm5 trigonal bipyramids.
Tm2S3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 8-coordinate geometry to two equivalent S(1), three equivalent S(2), and three equivalent S(3) atoms. Both Tm(1)-S(1) bond lengths are 2.82 Å. There are two shorter (2.76 Å) and one longer (3.34 Å) Tm(1)-S(2) bond length. There are two shorter (2.79 Å) and one longer (2.80 Å) Tm(1)-S(3) bond length. In the second Tm site, Tm(2) is bonded to two equivalent S(2), two equivalent S(3), and three equivalent S(1) atoms to form a mixture of distorted edge and corner-sharing TmS7 pentagonal bipyramids. There is one shorter (2.75 Å) and one longer (2.77 Å) Tm(2)-S(2) bond length. Both Tm(2)-S(3) bond lengths are 2.73 Å. There are two shorter (2.70 Å) and one longer (2.76 Å) Tm(2)-S(1) bond length. There are three inequivalent S sites. In the first S site, S(1) is bonded to two equivalent Tm(1) and three equivalent Tm(2) atoms to form a mixture of edge and corner-sharing STm5 square pyramids. In the second S site, S(2) is bonded in a 5-coordinate geometry to two equivalent Tm(2) and three equivalent Tm(1) atoms. In the third S site, S(3) is bonded to two equivalent Tm(2) and three equivalent Tm(1) atoms to form a mixture of distorted edge and corner-sharing STm5 trigonal bipyramids.