Na2SeMoO6 crystallizes in the cubic P2_13 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted hexagonal planar geometry to three equivalent O(1) and three equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. Mo(1) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. Se(1) is bonded in a distorted T-shaped geometry to three equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Mo(1), and one Se(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one Mo(1) atom.
Na2SeMoO6 crystallizes in the cubic P2_13 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted hexagonal planar geometry to three equivalent O(1) and three equivalent O(2) atoms. All Na(1)-O(1) bond lengths are 2.47 Å. All Na(1)-O(2) bond lengths are 2.51 Å. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. All Na(2)-O(1) bond lengths are 2.62 Å. All Na(2)-O(2) bond lengths are 2.38 Å. Mo(1) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. All Mo(1)-O(1) bond lengths are 2.24 Å. All Mo(1)-O(2) bond lengths are 1.79 Å. Se(1) is bonded in a distorted T-shaped geometry to three equivalent O(1) atoms. All Se(1)-O(1) bond lengths are 1.74 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Mo(1), and one Se(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one Mo(1) atom.