U2Cu4As5 crystallizes in the tetragonal I4/mmm space group. U(1) is bonded to four equivalent Cu(1), four equivalent As(1), and four equivalent As(3) atoms to form distorted UCu4As8 cuboctahedra that share corners with four equivalent U(1)Cu4As8 cuboctahedra, corners with eight equivalent Cu(1)U2As4 tetrahedra, edges with four equivalent U(1)Cu4As8 cuboctahedra, edges with four equivalent Cu(1)U2As4 tetrahedra, and faces with four equivalent U(1)Cu4As8 cuboctahedra. Cu(1) is bonded to two equivalent U(1), two equivalent As(1), and two equivalent As(2) atoms to form distorted CuU2As4 tetrahedra that share corners with four equivalent U(1)Cu4As8 cuboctahedra, corners with eight equivalent Cu(1)U2As4 tetrahedra, edges with two equivalent U(1)Cu4As8 cuboctahedra, edges with three equivalent Cu(1)U2As4 tetrahedra, and faces with four equivalent Cu(1)U2As4 tetrahedra. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to four equivalent U(1) and four equivalent Cu(1) atoms. In the second As site, As(2) is bonded in a body-centered cubic geometry to eight equivalent Cu(1) atoms. In the third As site, As(3) is bonded in a 8-coordinate geometry to four equivalent U(1) and four equivalent As(3) atoms.
U2Cu4As5 crystallizes in the tetragonal I4/mmm space group. U(1) is bonded to four equivalent Cu(1), four equivalent As(1), and four equivalent As(3) atoms to form distorted UCu4As8 cuboctahedra that share corners with four equivalent U(1)Cu4As8 cuboctahedra, corners with eight equivalent Cu(1)U2As4 tetrahedra, edges with four equivalent U(1)Cu4As8 cuboctahedra, edges with four equivalent Cu(1)U2As4 tetrahedra, and faces with four equivalent U(1)Cu4As8 cuboctahedra. All U(1)-Cu(1) bond lengths are 3.14 Å. All U(1)-As(1) bond lengths are 2.94 Å. All U(1)-As(3) bond lengths are 3.00 Å. Cu(1) is bonded to two equivalent U(1), two equivalent As(1), and two equivalent As(2) atoms to form distorted CuU2As4 tetrahedra that share corners with four equivalent U(1)Cu4As8 cuboctahedra, corners with eight equivalent Cu(1)U2As4 tetrahedra, edges with two equivalent U(1)Cu4As8 cuboctahedra, edges with three equivalent Cu(1)U2As4 tetrahedra, and faces with four equivalent Cu(1)U2As4 tetrahedra. Both Cu(1)-As(1) bond lengths are 2.56 Å. Both Cu(1)-As(2) bond lengths are 2.44 Å. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to four equivalent U(1) and four equivalent Cu(1) atoms. In the second As site, As(2) is bonded in a body-centered cubic geometry to eight equivalent Cu(1) atoms. In the third As site, As(3) is bonded in a 8-coordinate geometry to four equivalent U(1) and four equivalent As(3) atoms. All As(3)-As(3) bond lengths are 2.82 Å.