Na5OsO6 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with three equivalent Na(1)O6 octahedra, edges with three equivalent Os(1)O6 octahedra, and edges with four equivalent Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-21°. In the second Na site, Na(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NaO6 octahedra that share corners with two equivalent Os(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Os(1)O6 octahedra, edges with three equivalent Na(2)O6 octahedra, edges with three equivalent Na(3)O6 octahedra, and edges with four equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-21°. In the third Na site, Na(3) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Os(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Os(1)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with six equivalent Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-16°. Os(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form OsO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Na(2)O6 octahedra, and edges with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Os(1) atom to form a mixture of distorted corner and edge-sharing ONa5Os octahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the second O site, O(2) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Os(1) atom to form a mixture of distorted corner and edge-sharing ONa5Os octahedra. The corner-sharing octahedral tilt angles range from 0-17°.
Na5OsO6 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with three equivalent Na(1)O6 octahedra, edges with three equivalent Os(1)O6 octahedra, and edges with four equivalent Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-21°. Both Na(1)-O(1) bond lengths are 2.32 Å. There are two shorter (2.30 Å) and two longer (2.34 Å) Na(1)-O(2) bond lengths. In the second Na site, Na(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NaO6 octahedra that share corners with two equivalent Os(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Os(1)O6 octahedra, edges with three equivalent Na(2)O6 octahedra, edges with three equivalent Na(3)O6 octahedra, and edges with four equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-21°. Both Na(2)-O(1) bond lengths are 2.36 Å. There are two shorter (2.30 Å) and two longer (2.52 Å) Na(2)-O(2) bond lengths. In the third Na site, Na(3) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with two equivalent Os(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Os(1)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with six equivalent Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-16°. Both Na(3)-O(1) bond lengths are 2.71 Å. All Na(3)-O(2) bond lengths are 2.27 Å. Os(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form OsO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Na(2)O6 octahedra, and edges with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. Both Os(1)-O(1) bond lengths are 1.87 Å. All Os(1)-O(2) bond lengths are 1.94 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Os(1) atom to form a mixture of distorted corner and edge-sharing ONa5Os octahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the second O site, O(2) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Os(1) atom to form a mixture of distorted corner and edge-sharing ONa5Os octahedra. The corner-sharing octahedral tilt angles range from 0-17°.