RbAc3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Rb(1) is bonded to twelve equivalent Ac(1) atoms to form RbAc12 cuboctahedra that share corners with six equivalent Rb(1)Ac12 cuboctahedra, corners with twelve equivalent Ac(1)Rb4Ac8 cuboctahedra, edges with eighteen equivalent Ac(1)Rb4Ac8 cuboctahedra, faces with eight equivalent Rb(1)Ac12 cuboctahedra, and faces with twelve equivalent Ac(1)Rb4Ac8 cuboctahedra. Ac(1) is bonded to four equivalent Rb(1) and eight equivalent Ac(1) atoms to form distorted AcRb4Ac8 cuboctahedra that share corners with four equivalent Rb(1)Ac12 cuboctahedra, corners with fourteen equivalent Ac(1)Rb4Ac8 cuboctahedra, edges with six equivalent Rb(1)Ac12 cuboctahedra, edges with twelve equivalent Ac(1)Rb4Ac8 cuboctahedra, faces with four equivalent Rb(1)Ac12 cuboctahedra, and faces with sixteen equivalent Ac(1)Rb4Ac8 cuboctahedra.
RbAc3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Rb(1) is bonded to twelve equivalent Ac(1) atoms to form RbAc12 cuboctahedra that share corners with six equivalent Rb(1)Ac12 cuboctahedra, corners with twelve equivalent Ac(1)Rb4Ac8 cuboctahedra, edges with eighteen equivalent Ac(1)Rb4Ac8 cuboctahedra, faces with eight equivalent Rb(1)Ac12 cuboctahedra, and faces with twelve equivalent Ac(1)Rb4Ac8 cuboctahedra. There are six shorter (4.15 Å) and six longer (4.20 Å) Rb(1)-Ac(1) bond lengths. Ac(1) is bonded to four equivalent Rb(1) and eight equivalent Ac(1) atoms to form distorted AcRb4Ac8 cuboctahedra that share corners with four equivalent Rb(1)Ac12 cuboctahedra, corners with fourteen equivalent Ac(1)Rb4Ac8 cuboctahedra, edges with six equivalent Rb(1)Ac12 cuboctahedra, edges with twelve equivalent Ac(1)Rb4Ac8 cuboctahedra, faces with four equivalent Rb(1)Ac12 cuboctahedra, and faces with sixteen equivalent Ac(1)Rb4Ac8 cuboctahedra. There are a spread of Ac(1)-Ac(1) bond distances ranging from 4.01-4.38 Å.