Materials Data on CsAc3 by Materials Project
CsAc3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Cs is bonded to twelve Ac atoms to form CsAc12 cuboctahedra that share corners with six equivalent CsAc12 cuboctahedra, corners with twelve AcCs4Ac8 cuboctahedra, edges with eighteen AcCs4Ac8 cuboctahedra, faces with eight equivalent CsAc12 cuboctahedra, and faces with twelve AcCs4Ac8 cuboctahedra. There are six shorter (4.15 Å) and six longer (4.22 Å) Cs–Ac bond lengths. There are three inequivalent Ac sites. In the first Ac site, Ac is bonded to four equivalent Cs and eight Ac atoms to form distorted AcCs4Ac8 cuboctahedra that share corners with four equivalent CsAc12 cuboctahedra, corners with fourteen equivalent AcCs4Ac8 cuboctahedra, edges with six equivalent CsAc12 cuboctahedra, edges with twelve AcCs4Ac8 cuboctahedra, faces with four equivalent CsAc12 cuboctahedra, and faces with sixteen AcCs4Ac8 cuboctahedra. There are a spread of Ac–Ac bond distances ranging from 4.02–4.40 Å. In the second Ac site, Ac is bonded to four equivalent Cs and eight Ac atoms to form distorted AcCs4Ac8 cuboctahedra that share corners with four equivalent CsAc12 cuboctahedra, corners with fourteen AcCs4Ac8 cuboctahedra, edges with six equivalent CsAc12 cuboctahedra, edges with twelve AcCs4Ac8 cuboctahedra, faces with four equivalent CsAc12 cuboctahedra, and faces with sixteen AcCs4Ac8 cuboctahedra. There are a spread of Ac–Ac bond distances ranging from 4.02–4.40 Å. In the third Ac site, Ac is bonded to four equivalent Cs and eight Ac atoms to form distorted AcCs4Ac8 cuboctahedra that share corners with four equivalent CsAc12 cuboctahedra, corners with fourteen AcCs4Ac8 cuboctahedra, edges with six equivalent CsAc12 cuboctahedra, edges with twelve AcCs4Ac8 cuboctahedra, faces with four equivalent CsAc12 cuboctahedra, and faces with sixteen AcCs4Ac8 cuboctahedra.