Y3Cu2Ga9 crystallizes in the orthorhombic Immm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 12-coordinate geometry to two equivalent Cu(1), two equivalent Ga(3), four equivalent Ga(1), and four equivalent Ga(2) atoms. In the second Y site, Y(2) is bonded to four equivalent Cu(1), four equivalent Ga(2), and eight equivalent Ga(1) atoms to form distorted YGa12Cu4 cuboctahedra that share corners with four equivalent Ga(3)Y4Ga4Cu4 cuboctahedra, faces with two equivalent Y(2)Ga12Cu4 cuboctahedra, and faces with two equivalent Ga(3)Y4Ga4Cu4 cuboctahedra. Cu(1) is bonded in a 12-coordinate geometry to two equivalent Y(1), two equivalent Y(2), two equivalent Ga(1), two equivalent Ga(3), 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 two equivalent Y(1), two equivalent Y(2), one Cu(1), one Ga(1), and three equivalent Ga(2) atoms. In the second Ga site, Ga(2) is bonded in a 9-coordinate geometry to one Y(2), two equivalent Y(1), two equivalent Cu(1), one Ga(3), and three equivalent Ga(1) atoms. In the third Ga site, Ga(3) is bonded to four equivalent Y(1), four equivalent Cu(1), and four equivalent Ga(2) atoms to form GaY4Ga4Cu4 cuboctahedra that share corners with four equivalent Y(2)Ga12Cu4 cuboctahedra, faces with two equivalent Y(2)Ga12Cu4 cuboctahedra, and faces with two equivalent Ga(3)Y4Ga4Cu4 cuboctahedra.
Y3Cu2Ga9 crystallizes in the orthorhombic Immm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 12-coordinate geometry to two equivalent Cu(1), two equivalent Ga(3), four equivalent Ga(1), and four equivalent Ga(2) atoms. Both Y(1)-Cu(1) bond lengths are 3.08 Å. Both Y(1)-Ga(3) bond lengths are 3.02 Å. All Y(1)-Ga(1) bond lengths are 3.09 Å. All Y(1)-Ga(2) bond lengths are 3.08 Å. In the second Y site, Y(2) is bonded to four equivalent Cu(1), four equivalent Ga(2), and eight equivalent Ga(1) atoms to form distorted YGa12Cu4 cuboctahedra that share corners with four equivalent Ga(3)Y4Ga4Cu4 cuboctahedra, faces with two equivalent Y(2)Ga12Cu4 cuboctahedra, and faces with two equivalent Ga(3)Y4Ga4Cu4 cuboctahedra. All Y(2)-Cu(1) bond lengths are 3.46 Å. All Y(2)-Ga(2) bond lengths are 3.17 Å. All Y(2)-Ga(1) bond lengths are 3.13 Å. Cu(1) is bonded in a 12-coordinate geometry to two equivalent Y(1), two equivalent Y(2), two equivalent Ga(1), two equivalent Ga(3), and four equivalent Ga(2) atoms. Both Cu(1)-Ga(1) bond lengths are 2.47 Å. Both Cu(1)-Ga(3) bond lengths are 3.00 Å. All Cu(1)-Ga(2) bond lengths are 2.61 Å. There are three inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(2), one Cu(1), one Ga(1), and three equivalent Ga(2) atoms. The Ga(1)-Ga(1) bond length is 2.53 Å. There are two shorter (2.58 Å) and one longer (2.68 Å) Ga(1)-Ga(2) bond length. In the second Ga site, Ga(2) is bonded in a 9-coordinate geometry to one Y(2), two equivalent Y(1), two equivalent Cu(1), one Ga(3), and three equivalent Ga(1) atoms. The Ga(2)-Ga(3) bond length is 2.70 Å. In the third Ga site, Ga(3) is bonded to four equivalent Y(1), four equivalent Cu(1), and four equivalent Ga(2) atoms to form GaY4Ga4Cu4 cuboctahedra that share corners with four equivalent Y(2)Ga12Cu4 cuboctahedra, faces with two equivalent Y(2)Ga12Cu4 cuboctahedra, and faces with two equivalent Ga(3)Y4Ga4Cu4 cuboctahedra.