Materials Data on Na3Cu by Materials Project
Na3Cu is alpha bismuth trifluoride 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 in a 4-coordinate geometry to four equivalent Na and four equivalent Cu atoms. All Na–Na bond lengths are 3.24 Å. All Na–Cu bond lengths are 3.24 Å. In the second Na site, Na is bonded to eight equivalent Na and four equivalent Cu atoms to form NaNa8Cu4 cuboctahedra that share corners with four equivalent NaNa8Cu4 cuboctahedra, corners with eight equivalent CuNa12 cuboctahedra, edges with eight equivalent NaNa8Cu4 cuboctahedra, faces with four equivalent NaNa8Cu4 cuboctahedra, and faces with six equivalent CuNa12 cuboctahedra. All Na–Cu bond lengths are 3.44 Å. Cu is bonded to twelve Na atoms to form CuNa12 cuboctahedra that share corners with four equivalent CuNa12 cuboctahedra, corners with eight equivalent NaNa8Cu4 cuboctahedra, edges with eight equivalent CuNa12 cuboctahedra, faces with four equivalent CuNa12 cuboctahedra, and faces with six equivalent NaNa8Cu4 cuboctahedra.