Na2UF6 is Fluorite-derived structured and crystallizes in the monoclinic C2/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a body-centered cubic geometry to two equivalent F(2), two equivalent F(3), and four equivalent F(1) atoms. In the second Na site, Na(2) is bonded in a body-centered cubic geometry to two equivalent F(1), two equivalent F(3), and four equivalent F(2) atoms. U(1) is bonded in a body-centered cubic geometry to two equivalent F(1), two equivalent F(2), and four equivalent F(3) atoms. There are three inequivalent F sites. In the first F site, F(1) is bonded to one Na(2), two equivalent Na(1), and one U(1) atom to form FNa3U tetrahedra that share corners with four equivalent F(1)Na3U tetrahedra, corners with six equivalent F(3)Na2U2 tetrahedra, corners with six equivalent F(2)Na3U tetrahedra, edges with two equivalent F(3)Na2U2 tetrahedra, edges with two equivalent F(1)Na3U tetrahedra, and edges with two equivalent F(2)Na3U tetrahedra. In the second F site, F(2) is bonded to one Na(1), two equivalent Na(2), and one U(1) atom to form FNa3U tetrahedra that share corners with four equivalent F(2)Na3U tetrahedra, corners with six equivalent F(3)Na2U2 tetrahedra, corners with six equivalent F(1)Na3U tetrahedra, edges with two equivalent F(3)Na2U2 tetrahedra, edges with two equivalent F(1)Na3U tetrahedra, and edges with two equivalent F(2)Na3U tetrahedra. In the third F site, F(3) is bonded to one Na(1), one Na(2), and two equivalent U(1) atoms to form FNa2U2 tetrahedra that share corners with four equivalent F(3)Na2U2 tetrahedra, corners with six equivalent F(1)Na3U tetrahedra, corners with six equivalent F(2)Na3U tetrahedra, edges with two equivalent F(3)Na2U2 tetrahedra, edges with two equivalent F(1)Na3U tetrahedra, and edges with two equivalent F(2)Na3U tetrahedra.
Na2UF6 is Fluorite-derived structured and crystallizes in the monoclinic C2/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a body-centered cubic geometry to two equivalent F(2), two equivalent F(3), and four equivalent F(1) atoms. Both Na(1)-F(2) bond lengths are 2.37 Å. Both Na(1)-F(3) bond lengths are 2.43 Å. There are two shorter (2.41 Å) and two longer (2.44 Å) Na(1)-F(1) bond lengths. In the second Na site, Na(2) is bonded in a body-centered cubic geometry to two equivalent F(1), two equivalent F(3), and four equivalent F(2) atoms. Both Na(2)-F(1) bond lengths are 2.39 Å. Both Na(2)-F(3) bond lengths are 2.43 Å. There are two shorter (2.39 Å) and two longer (2.42 Å) Na(2)-F(2) bond lengths. U(1) is bonded in a body-centered cubic geometry to two equivalent F(1), two equivalent F(2), and four equivalent F(3) atoms. Both U(1)-F(1) bond lengths are 2.19 Å. Both U(1)-F(2) bond lengths are 2.23 Å. There are two shorter (2.35 Å) and two longer (2.39 Å) U(1)-F(3) bond lengths. There are three inequivalent F sites. In the first F site, F(1) is bonded to one Na(2), two equivalent Na(1), and one U(1) atom to form FNa3U tetrahedra that share corners with four equivalent F(1)Na3U tetrahedra, corners with six equivalent F(3)Na2U2 tetrahedra, corners with six equivalent F(2)Na3U tetrahedra, edges with two equivalent F(3)Na2U2 tetrahedra, edges with two equivalent F(1)Na3U tetrahedra, and edges with two equivalent F(2)Na3U tetrahedra. In the second F site, F(2) is bonded to one Na(1), two equivalent Na(2), and one U(1) atom to form FNa3U tetrahedra that share corners with four equivalent F(2)Na3U tetrahedra, corners with six equivalent F(3)Na2U2 tetrahedra, corners with six equivalent F(1)Na3U tetrahedra, edges with two equivalent F(3)Na2U2 tetrahedra, edges with two equivalent F(1)Na3U tetrahedra, and edges with two equivalent F(2)Na3U tetrahedra. In the third F site, F(3) is bonded to one Na(1), one Na(2), and two equivalent U(1) atoms to form FNa2U2 tetrahedra that share corners with four equivalent F(3)Na2U2 tetrahedra, corners with six equivalent F(1)Na3U tetrahedra, corners with six equivalent F(2)Na3U tetrahedra, edges with two equivalent F(3)Na2U2 tetrahedra, edges with two equivalent F(1)Na3U tetrahedra, and edges with two equivalent F(2)Na3U tetrahedra.