Tm3Cu4Sn4 crystallizes in the monoclinic C2/m space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 6-coordinate geometry to four equivalent Cu(2), two equivalent Sn(1), and four equivalent Sn(2) atoms. In the second Tm site, Tm(2) is bonded in a 13-coordinate geometry to three equivalent Cu(1), three equivalent Cu(2), three equivalent Sn(1), and four equivalent Sn(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 8-coordinate geometry to three equivalent Tm(2), one Cu(2), one Sn(2), and three equivalent Sn(1) atoms. In the second Cu site, Cu(2) is bonded in a 10-coordinate geometry to two equivalent Tm(1), three equivalent Tm(2), one Cu(1), one Sn(2), and three equivalent Sn(1) atoms. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 9-coordinate geometry to one Tm(1), three equivalent Tm(2), three equivalent Cu(1), and three equivalent Cu(2) atoms. In the second Sn site, Sn(2) is bonded in a 9-coordinate geometry to two equivalent Tm(1), four equivalent Tm(2), one Cu(1), one Cu(2), and one Sn(2) atom.
Tm3Cu4Sn4 crystallizes in the monoclinic C2/m space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 6-coordinate geometry to four equivalent Cu(2), two equivalent Sn(1), and four equivalent Sn(2) atoms. All Tm(1)-Cu(2) bond lengths are 3.41 Å. Both Tm(1)-Sn(1) bond lengths are 3.15 Å. All Tm(1)-Sn(2) bond lengths are 3.00 Å. In the second Tm site, Tm(2) is bonded in a 13-coordinate geometry to three equivalent Cu(1), three equivalent Cu(2), three equivalent Sn(1), and four equivalent Sn(2) atoms. There is one shorter (3.03 Å) and two longer (3.20 Å) Tm(2)-Cu(1) bond lengths. There are two shorter (3.08 Å) and one longer (3.28 Å) Tm(2)-Cu(2) bond length. There are two shorter (3.12 Å) and one longer (3.49 Å) Tm(2)-Sn(1) bond length. There are two shorter (3.19 Å) and two longer (3.26 Å) Tm(2)-Sn(2) bond lengths. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 8-coordinate geometry to three equivalent Tm(2), one Cu(2), one Sn(2), and three equivalent Sn(1) atoms. The Cu(1)-Cu(2) bond length is 2.61 Å. The Cu(1)-Sn(2) bond length is 2.62 Å. There is one shorter (2.66 Å) and two longer (2.67 Å) Cu(1)-Sn(1) bond lengths. In the second Cu site, Cu(2) is bonded in a 10-coordinate geometry to two equivalent Tm(1), three equivalent Tm(2), one Cu(1), one Sn(2), and three equivalent Sn(1) atoms. The Cu(2)-Sn(2) bond length is 2.59 Å. There are two shorter (2.61 Å) and one longer (2.73 Å) Cu(2)-Sn(1) bond length. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 9-coordinate geometry to one Tm(1), three equivalent Tm(2), three equivalent Cu(1), and three equivalent Cu(2) atoms. In the second Sn site, Sn(2) is bonded in a 9-coordinate geometry to two equivalent Tm(1), four equivalent Tm(2), one Cu(1), one Cu(2), and one Sn(2) atom. The Sn(2)-Sn(2) bond length is 2.82 Å.