Tb2Cu3Ga5 crystallizes in the tetragonal P-4m2 space group. Tb(1) is bonded in a 16-coordinate geometry to two equivalent Cu(1), two equivalent Cu(2), two equivalent Cu(3), two equivalent Ga(3), four equivalent Ga(1), and four equivalent Ga(2) atoms. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to four equivalent Tb(1) and four equivalent Ga(2) atoms. In the second Cu site, Cu(2) is bonded to four equivalent Tb(1), four equivalent Ga(1), and four equivalent Ga(3) atoms to form distorted CuTb4Ga8 cuboctahedra that share corners with four equivalent Cu(2)Tb4Ga8 cuboctahedra, faces with four equivalent Cu(2)Tb4Ga8 cuboctahedra, and faces with four equivalent Ga(3)Tb4Ga4Cu4 cuboctahedra. In the third Cu site, Cu(3) is bonded in a 4-coordinate geometry to four equivalent Tb(1) and four equivalent Ga(2) atoms. There are three inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 9-coordinate geometry to four equivalent Tb(1), two equivalent Cu(2), one Ga(2), and two equivalent Ga(3) atoms. In the second Ga site, Ga(2) is bonded in a 9-coordinate geometry to four equivalent Tb(1), two equivalent Cu(1), two equivalent Cu(3), and one Ga(1) atom. In the third Ga site, Ga(3) is bonded to four equivalent Tb(1), four equivalent Cu(2), and four equivalent Ga(1) atoms to form GaTb4Ga4Cu4 cuboctahedra that share corners with four equivalent Ga(3)Tb4Ga4Cu4 cuboctahedra, faces with four equivalent Cu(2)Tb4Ga8 cuboctahedra, and faces with four equivalent Ga(3)Tb4Ga4Cu4 cuboctahedra.
Tb2Cu3Ga5 crystallizes in the tetragonal P-4m2 space group. Tb(1) is bonded in a 16-coordinate geometry to two equivalent Cu(1), two equivalent Cu(2), two equivalent Cu(3), two equivalent Ga(3), four equivalent Ga(1), and four equivalent Ga(2) atoms. Both Tb(1)-Cu(1) bond lengths are 3.22 Å. Both Tb(1)-Cu(2) bond lengths are 3.35 Å. Both Tb(1)-Cu(3) bond lengths are 3.22 Å. Both Tb(1)-Ga(3) bond lengths are 3.35 Å. All Tb(1)-Ga(1) bond lengths are 3.14 Å. All Tb(1)-Ga(2) bond lengths are 3.14 Å. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to four equivalent Tb(1) and four equivalent Ga(2) atoms. All Cu(1)-Ga(2) bond lengths are 2.40 Å. In the second Cu site, Cu(2) is bonded to four equivalent Tb(1), four equivalent Ga(1), and four equivalent Ga(3) atoms to form distorted CuTb4Ga8 cuboctahedra that share corners with four equivalent Cu(2)Tb4Ga8 cuboctahedra, faces with four equivalent Cu(2)Tb4Ga8 cuboctahedra, and faces with four equivalent Ga(3)Tb4Ga4Cu4 cuboctahedra. All Cu(2)-Ga(1) bond lengths are 2.50 Å. All Cu(2)-Ga(3) bond lengths are 2.90 Å. In the third Cu site, Cu(3) is bonded in a 4-coordinate geometry to four equivalent Tb(1) and four equivalent Ga(2) atoms. All Cu(3)-Ga(2) bond lengths are 2.40 Å. There are three inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 9-coordinate geometry to four equivalent Tb(1), two equivalent Cu(2), one Ga(2), and two equivalent Ga(3) atoms. The Ga(1)-Ga(2) bond length is 2.44 Å. Both Ga(1)-Ga(3) bond lengths are 2.50 Å. In the second Ga site, Ga(2) is bonded in a 9-coordinate geometry to four equivalent Tb(1), two equivalent Cu(1), two equivalent Cu(3), and one Ga(1) atom. In the third Ga site, Ga(3) is bonded to four equivalent Tb(1), four equivalent Cu(2), and four equivalent Ga(1) atoms to form GaTb4Ga4Cu4 cuboctahedra that share corners with four equivalent Ga(3)Tb4Ga4Cu4 cuboctahedra, faces with four equivalent Cu(2)Tb4Ga8 cuboctahedra, and faces with four equivalent Ga(3)Tb4Ga4Cu4 cuboctahedra.