Na4PtO4 crystallizes in the monoclinic C2/m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and three equivalent O(2) atoms to form distorted NaO5 trigonal bipyramids that share corners with two equivalent Pt(1)O6 octahedra, edges with three equivalent Pt(1)O6 octahedra, and edges with four equivalent Na(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 14°. In the second Na site, Na(2) is bonded in a distorted see-saw-like geometry to one O(2) and three equivalent O(1) atoms. Pt(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form PtO6 octahedra that share corners with four equivalent Na(1)O5 trigonal bipyramids, edges with two equivalent Pt(1)O6 octahedra, and edges with six equivalent Na(1)O5 trigonal bipyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), three equivalent Na(2), and one Pt(1) atom to form ONa5Pt octahedra that share  a cornercorner with one O(1)Na5Pt octahedra, corners with three equivalent O(2)Na4Pt2 octahedra, edges with four equivalent O(1)Na5Pt octahedra, and edges with five equivalent O(2)Na4Pt2 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. In the second O site, O(2) is bonded to one Na(2), three equivalent Na(1), and two equivalent Pt(1) atoms to form ONa4Pt2 octahedra that share corners with two equivalent O(2)Na4Pt2 octahedra, corners with three equivalent O(1)Na5Pt octahedra, edges with five equivalent O(2)Na4Pt2 octahedra, and edges with five equivalent O(1)Na5Pt octahedra. The corner-sharing octahedral tilt angles range from 0-13°.
Na4PtO4 crystallizes in the monoclinic C2/m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(1) and three equivalent O(2) atoms to form distorted NaO5 trigonal bipyramids that share corners with two equivalent Pt(1)O6 octahedra, edges with three equivalent Pt(1)O6 octahedra, and edges with four equivalent Na(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 14°. Both Na(1)-O(1) bond lengths are 2.29 Å. There is one shorter (2.29 Å) and two longer (2.53 Å) Na(1)-O(2) bond lengths. In the second Na site, Na(2) is bonded in a distorted see-saw-like geometry to one O(2) and three equivalent O(1) atoms. The Na(2)-O(2) bond length is 2.25 Å. There are two shorter (2.23 Å) and one longer (2.36 Å) Na(2)-O(1) bond length. Pt(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form PtO6 octahedra that share corners with four equivalent Na(1)O5 trigonal bipyramids, edges with two equivalent Pt(1)O6 octahedra, and edges with six equivalent Na(1)O5 trigonal bipyramids. Both Pt(1)-O(1) bond lengths are 2.12 Å. All Pt(1)-O(2) bond lengths are 2.11 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), three equivalent Na(2), and one Pt(1) atom to form ONa5Pt octahedra that share  a cornercorner with one O(1)Na5Pt octahedra, corners with three equivalent O(2)Na4Pt2 octahedra, edges with four equivalent O(1)Na5Pt octahedra, and edges with five equivalent O(2)Na4Pt2 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. In the second O site, O(2) is bonded to one Na(2), three equivalent Na(1), and two equivalent Pt(1) atoms to form ONa4Pt2 octahedra that share corners with two equivalent O(2)Na4Pt2 octahedra, corners with three equivalent O(1)Na5Pt octahedra, edges with five equivalent O(2)Na4Pt2 octahedra, and edges with five equivalent O(1)Na5Pt octahedra. The corner-sharing octahedral tilt angles range from 0-13°.