SrCu3GaSe4 crystallizes in the cubic P-43m space group. Sr(1) is bonded to four equivalent Se(1) atoms to form SrSe4 tetrahedra that share corners with four equivalent Ga(1)Se4 tetrahedra and corners with twelve equivalent Cu(1)Se4 tetrahedra. Cu(1) is bonded to four equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Sr(1)Se4 tetrahedra, corners with eight equivalent Cu(1)Se4 tetrahedra, and edges with two equivalent Ga(1)Se4 tetrahedra. Ga(1) is bonded to four equivalent Se(1) atoms to form GaSe4 tetrahedra that share corners with four equivalent Sr(1)Se4 tetrahedra and edges with six equivalent Cu(1)Se4 tetrahedra. Se(1) is bonded to one Sr(1), three equivalent Cu(1), and one Ga(1) atom to form a mixture of distorted edge and corner-sharing SeSrGaCu3 trigonal bipyramids.
SrCu3GaSe4 crystallizes in the cubic P-43m space group. Sr(1) is bonded to four equivalent Se(1) atoms to form SrSe4 tetrahedra that share corners with four equivalent Ga(1)Se4 tetrahedra and corners with twelve equivalent Cu(1)Se4 tetrahedra. All Sr(1)-Se(1) bond lengths are 2.88 Å. Cu(1) is bonded to four equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Sr(1)Se4 tetrahedra, corners with eight equivalent Cu(1)Se4 tetrahedra, and edges with two equivalent Ga(1)Se4 tetrahedra. All Cu(1)-Se(1) bond lengths are 2.56 Å. Ga(1) is bonded to four equivalent Se(1) atoms to form GaSe4 tetrahedra that share corners with four equivalent Sr(1)Se4 tetrahedra and edges with six equivalent Cu(1)Se4 tetrahedra. All Ga(1)-Se(1) bond lengths are 2.39 Å. Se(1) is bonded to one Sr(1), three equivalent Cu(1), and one Ga(1) atom to form a mixture of distorted edge and corner-sharing SeSrGaCu3 trigonal bipyramids.