Na3CuF6 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form NaF6 octahedra that share corners with six equivalent Cu(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 34-40°. In the second Na site, Na(2) is bonded in a 8-coordinate geometry to two equivalent F(2), three equivalent F(1), and three equivalent F(3) atoms. Cu(1) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form CuF6 octahedra that share corners with six equivalent Na(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 34-40°. There are three inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to one Na(1), three equivalent Na(2), and one Cu(1) atom. In the second F site, F(2) is bonded in a distorted see-saw-like geometry to one Na(1), two equivalent Na(2), and one Cu(1) atom. In the third F site, F(3) is bonded in a 5-coordinate geometry to one Na(1), three equivalent Na(2), and one Cu(1) atom.
Na3CuF6 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form NaF6 octahedra that share corners with six equivalent Cu(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 34-40°. Both Na(1)-F(1) bond lengths are 2.25 Å. Both Na(1)-F(2) bond lengths are 2.24 Å. Both Na(1)-F(3) bond lengths are 2.19 Å. In the second Na site, Na(2) is bonded in a 8-coordinate geometry to two equivalent F(2), three equivalent F(1), and three equivalent F(3) atoms. There is one shorter (2.26 Å) and one longer (2.30 Å) Na(2)-F(2) bond length. There are a spread of Na(2)-F(1) bond distances ranging from 2.28-2.87 Å. There are a spread of Na(2)-F(3) bond distances ranging from 2.28-2.70 Å. Cu(1) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form CuF6 octahedra that share corners with six equivalent Na(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 34-40°. Both Cu(1)-F(1) bond lengths are 1.90 Å. Both Cu(1)-F(2) bond lengths are 1.89 Å. Both Cu(1)-F(3) bond lengths are 1.89 Å. There are three inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to one Na(1), three equivalent Na(2), and one Cu(1) atom. In the second F site, F(2) is bonded in a distorted see-saw-like geometry to one Na(1), two equivalent Na(2), and one Cu(1) atom. In the third F site, F(3) is bonded in a 5-coordinate geometry to one Na(1), three equivalent Na(2), and one Cu(1) atom.