Materials Data on Na3Be by Materials Project
Na3Be is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to eight Na and four equivalent Be atoms to form distorted NaNa8Be4 cuboctahedra that share corners with twelve equivalent NaNa8Be4 cuboctahedra, edges with eight equivalent BeNa12 cuboctahedra, edges with sixteen NaNa8Be4 cuboctahedra, faces with four equivalent BeNa12 cuboctahedra, and faces with fourteen NaNa8Be4 cuboctahedra. There are four shorter (3.30 Å) and four longer (3.33 Å) Na–Na bond lengths. All Na–Be bond lengths are 3.33 Å. In the second Na site, Na is bonded to eight equivalent Na and four equivalent Be atoms to form distorted NaNa8Be4 cuboctahedra that share corners with four equivalent NaNa8Be4 cuboctahedra, corners with eight equivalent BeNa12 cuboctahedra, edges with twenty-four NaNa8Be4 cuboctahedra, faces with six equivalent BeNa12 cuboctahedra, and faces with twelve NaNa8Be4 cuboctahedra. All Na–Be bond lengths are 3.30 Å. Be is bonded to twelve Na atoms to form BeNa12 cuboctahedra that share corners with four equivalent BeNa12 cuboctahedra, corners with eight equivalent NaNa8Be4 cuboctahedra, edges with eight equivalent BeNa12 cuboctahedra, edges with sixteen equivalent NaNa8Be4 cuboctahedra, faces with four equivalent BeNa12 cuboctahedra, and faces with fourteen NaNa8Be4 cuboctahedra.