Rb3Ac is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to four equivalent Rb(1), four equivalent Rb(2), and four equivalent Ac(1) atoms to form RbRb8Ac4 cuboctahedra that share corners with twelve equivalent Rb(1)Rb8Ac4 cuboctahedra, edges with eight equivalent Rb(1)Rb8Ac4 cuboctahedra, edges with eight equivalent Ac(1)Rb12 cuboctahedra, faces with four equivalent Ac(1)Rb12 cuboctahedra, and faces with ten equivalent Rb(1)Rb8Ac4 cuboctahedra. In the second Rb site, Rb(2) is bonded in a distorted square co-planar geometry to eight equivalent Rb(1) and four equivalent Ac(1) atoms. Ac(1) is bonded to four equivalent Rb(2) and eight equivalent Rb(1) atoms to form AcRb12 cuboctahedra that share corners with four equivalent Ac(1)Rb12 cuboctahedra, edges with eight equivalent Ac(1)Rb12 cuboctahedra, edges with sixteen equivalent Rb(1)Rb8Ac4 cuboctahedra, faces with four equivalent Ac(1)Rb12 cuboctahedra, and faces with eight equivalent Rb(1)Rb8Ac4 cuboctahedra.
Rb3Ac is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to four equivalent Rb(1), four equivalent Rb(2), and four equivalent Ac(1) atoms to form RbRb8Ac4 cuboctahedra that share corners with twelve equivalent Rb(1)Rb8Ac4 cuboctahedra, edges with eight equivalent Rb(1)Rb8Ac4 cuboctahedra, edges with eight equivalent Ac(1)Rb12 cuboctahedra, faces with four equivalent Ac(1)Rb12 cuboctahedra, and faces with ten equivalent Rb(1)Rb8Ac4 cuboctahedra. All Rb(1)-Rb(1) bond lengths are 4.48 Å. All Rb(1)-Rb(2) bond lengths are 4.77 Å. All Rb(1)-Ac(1) bond lengths are 4.77 Å. In the second Rb site, Rb(2) is bonded in a distorted square co-planar geometry to eight equivalent Rb(1) and four equivalent Ac(1) atoms. All Rb(2)-Ac(1) bond lengths are 4.48 Å. Ac(1) is bonded to four equivalent Rb(2) and eight equivalent Rb(1) atoms to form AcRb12 cuboctahedra that share corners with four equivalent Ac(1)Rb12 cuboctahedra, edges with eight equivalent Ac(1)Rb12 cuboctahedra, edges with sixteen equivalent Rb(1)Rb8Ac4 cuboctahedra, faces with four equivalent Ac(1)Rb12 cuboctahedra, and faces with eight equivalent Rb(1)Rb8Ac4 cuboctahedra.