Cu3Ga is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Cu(1), four equivalent Cu(2), and four equivalent Ga(1) atoms to form CuGa4Cu8 cuboctahedra that share corners with twelve equivalent Cu(1)Ga4Cu8 cuboctahedra, edges with eight equivalent Cu(1)Ga4Cu8 cuboctahedra, edges with eight equivalent Cu(2)Ga4Cu8 cuboctahedra, edges with eight equivalent Ga(1)Cu12 cuboctahedra, faces with four equivalent Cu(2)Ga4Cu8 cuboctahedra, faces with four equivalent Ga(1)Cu12 cuboctahedra, and faces with ten equivalent Cu(1)Ga4Cu8 cuboctahedra. In the second Cu site, Cu(2) is bonded to eight equivalent Cu(1) and four equivalent Ga(1) atoms to form CuGa4Cu8 cuboctahedra that share corners with four equivalent Cu(2)Ga4Cu8 cuboctahedra, corners with eight equivalent Ga(1)Cu12 cuboctahedra, edges with eight equivalent Cu(2)Ga4Cu8 cuboctahedra, edges with sixteen equivalent Cu(1)Ga4Cu8 cuboctahedra, faces with four equivalent Cu(2)Ga4Cu8 cuboctahedra, faces with six equivalent Ga(1)Cu12 cuboctahedra, and faces with eight equivalent Cu(1)Ga4Cu8 cuboctahedra. Ga(1) is bonded to four equivalent Cu(2) and eight equivalent Cu(1) atoms to form GaCu12 cuboctahedra that share corners with four equivalent Ga(1)Cu12 cuboctahedra, corners with eight equivalent Cu(2)Ga4Cu8 cuboctahedra, edges with eight equivalent Ga(1)Cu12 cuboctahedra, edges with sixteen equivalent Cu(1)Ga4Cu8 cuboctahedra, faces with four equivalent Ga(1)Cu12 cuboctahedra, faces with six equivalent Cu(2)Ga4Cu8 cuboctahedra, and faces with eight equivalent Cu(1)Ga4Cu8 cuboctahedra.
Cu3Ga is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Cu(1), four equivalent Cu(2), and four equivalent Ga(1) atoms to form CuGa4Cu8 cuboctahedra that share corners with twelve equivalent Cu(1)Ga4Cu8 cuboctahedra, edges with eight equivalent Cu(1)Ga4Cu8 cuboctahedra, edges with eight equivalent Cu(2)Ga4Cu8 cuboctahedra, edges with eight equivalent Ga(1)Cu12 cuboctahedra, faces with four equivalent Cu(2)Ga4Cu8 cuboctahedra, faces with four equivalent Ga(1)Cu12 cuboctahedra, and faces with ten equivalent Cu(1)Ga4Cu8 cuboctahedra. All Cu(1)-Cu(1) bond lengths are 2.57 Å. All Cu(1)-Cu(2) bond lengths are 2.59 Å. All Cu(1)-Ga(1) bond lengths are 2.59 Å. In the second Cu site, Cu(2) is bonded to eight equivalent Cu(1) and four equivalent Ga(1) atoms to form CuGa4Cu8 cuboctahedra that share corners with four equivalent Cu(2)Ga4Cu8 cuboctahedra, corners with eight equivalent Ga(1)Cu12 cuboctahedra, edges with eight equivalent Cu(2)Ga4Cu8 cuboctahedra, edges with sixteen equivalent Cu(1)Ga4Cu8 cuboctahedra, faces with four equivalent Cu(2)Ga4Cu8 cuboctahedra, faces with six equivalent Ga(1)Cu12 cuboctahedra, and faces with eight equivalent Cu(1)Ga4Cu8 cuboctahedra. All Cu(2)-Ga(1) bond lengths are 2.57 Å. Ga(1) is bonded to four equivalent Cu(2) and eight equivalent Cu(1) atoms to form GaCu12 cuboctahedra that share corners with four equivalent Ga(1)Cu12 cuboctahedra, corners with eight equivalent Cu(2)Ga4Cu8 cuboctahedra, edges with eight equivalent Ga(1)Cu12 cuboctahedra, edges with sixteen equivalent Cu(1)Ga4Cu8 cuboctahedra, faces with four equivalent Ga(1)Cu12 cuboctahedra, faces with six equivalent Cu(2)Ga4Cu8 cuboctahedra, and faces with eight equivalent Cu(1)Ga4Cu8 cuboctahedra.