Materials Data on K3Ac by Materials Project
K3Ac is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. K is bonded to eight equivalent K and four equivalent Ac atoms to form KK8Ac4 cuboctahedra that share corners with four equivalent AcK12 cuboctahedra, corners with fourteen equivalent KK8Ac4 cuboctahedra, edges with six equivalent AcK12 cuboctahedra, edges with twelve equivalent KK8Ac4 cuboctahedra, faces with four equivalent AcK12 cuboctahedra, and faces with sixteen equivalent KK8Ac4 cuboctahedra. There are two shorter (4.39 Å) and six longer (4.48 Å) K–K bond lengths. There are two shorter (4.44 Å) and two longer (4.46 Å) K–Ac bond lengths. Ac is bonded to twelve equivalent K atoms to form AcK12 cuboctahedra that share corners with six equivalent AcK12 cuboctahedra, corners with twelve equivalent KK8Ac4 cuboctahedra, edges with eighteen equivalent KK8Ac4 cuboctahedra, faces with eight equivalent AcK12 cuboctahedra, and faces with twelve equivalent KK8Ac4 cuboctahedra.