The material structure described by Na4SeO5 crystallizes in the triclinic P-1 space group. There are nine inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(3), one O(8), two equivalent O(6), and two equivalent O(9) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Se(1)O5 trigonal bipyramids,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with three equivalent Na(7)O6 octahedra,  an edgeedge with one Se(2)O5 square pyramid, and  an edgeedge with one Se(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 11-33°. In the second Na site, Na(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(7) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra,  a cornercorner with one Se(2)O5 square pyramid,  a cornercorner with one Se(1)O5 trigonal bipyramid,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with three equivalent Na(9)O6 octahedra, and edges with two equivalent Se(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 10-35°. In the third Na site, Na(3) is bonded to two equivalent O(10), two equivalent O(3), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Se(2)O5 square pyramids, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Na(9)O6 octahedra, edges with four equivalent Na(5)O6 octahedra, and edges with two equivalent Se(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 11-21°. In the fourth Na site, Na(4) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Se(2)O5 square pyramids, corners with two equivalent Se(1)O5 trigonal bipyramids, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Na(9)O6 octahedra, and edges with four equivalent Na(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-35°. In the fifth Na site, Na(5) is bonded to one O(3), one O(4), one O(7), one O(9), and two equivalent O(10) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(7)O6 octahedra, corners with two equivalent Na(9)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Se(2)O5 square pyramids, and  an edgeedge with one Se(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 10-26°. In the sixth Na site, Na(6) is bonded to one O(1), one O(5), one O(6), one O(8), and two equivalent O(2) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(7)O6 octahedra, corners with two equivalent Na(9)O6 octahedra,  a cornercorner with one Se(2)O5 square pyramid,  a cornercorner with one Se(1)O5 trigonal bipyramid,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(4)O6 octahedra,  an edgeedge with one Se(2)O5 square pyramid, and  an edgeedge with one Se(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 24-34°. In the seventh Na site, Na(7) is bonded to one O(10), one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form distorted NaO6 octahedra that share  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(6)O6 octahedra, corners with two equivalent Se(1)O5 trigonal bipyramids,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with three equivalent Na(1)O6 octahedra, and edges with two equivalent Se(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 10-33°. In the eighth Na site, Na(8) is bonded to one O(1), one O(3), one O(4), one O(6), one O(7), and one O(9) atom to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Se(2)O5 square pyramids,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, and edges with two equivalent Se(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 15-27°. In the ninth Na site, Na(9) is bonded to one O(1), one O(10), one O(2), one O(4), one O(5), and one O(7) atom to form distorted NaO6 octahedra that share  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(6)O6 octahedra,  a cornercorner with one Se(2)O5 square pyramid,  a cornercorner with one Se(1)O5 trigonal bipyramid,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with three equivalent Na(2)O6 octahedra,  an edgeedge with one Se(2)O5 square pyramid, and  an edgeedge with one Se(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 20-34°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(5), one O(6), one O(7), and one O(9) atom to form SeO5 trigonal bipyramids that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and edges with two equivalent Na(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-73°. In the second Se site, Se(2) is bonded to one O(10), one O(2), one O(3), one O(4), and one O(8) atom to form SeO5 square pyramids that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, and edges with two equivalent Na(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-72°. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Na(6), one Na(8), one Na(9), two equivalent Na(2), and one Se(1) atom to form distorted ONa5Se octahedra that share  a cornercorner with one O(3)Na5Se octahedra,  a cornercorner with one O(6)Na5Se octahedra,  a cornercorner with one O(7)Na5Se octahedra,  a cornercorner with one O(5)Na4Se trigonal bipyramid,  a cornercorner with one O(8)Na4Se trigonal bipyramid,  an edgeedge with one O(1)Na5Se octahedra,  an edgeedge with one O(6)Na5Se octahedra, edges with two equivalent O(4)Na5Se octahedra, edges with three equivalent O(7)Na5Se octahedra, and edges with two equivalent O(5)Na4Se trigonal bipyramids. The corner-sharing octahedral tilt angles range from 12-18°. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(4), one Na(7), one Na(9), two equivalent Na(6), and one Se(2) atom. In the third O site, O(3) is bonded to one Na(1), one Na(3), one Na(5), one Na(7), one Na(8), and one Se(2) atom to form ONa5Se octahedra that share  a cornercorner with one O(1)Na5Se octahedra,  a cornercorner with one O(3)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra,  a cornercorner with one O(8)Na4Se trigonal bipyramid,  an edgeedge with one O(7)Na5Se octahedra, edges with two equivalent O(4)Na5Se octahedra, edges with two equivalent O(6)Na5Se octahedra, and  an edgeedge with one O(8)Na4Se trigonal bipyramid. The corner-sharing octahedral tilt angles range from 0-13°. In the fourth O site, O(4) is bonded to one Na(2), one Na(3), one Na(5), one Na(8), one Na(9), and one Se(2) atom to form distorted ONa5Se octahedra that share  a cornercorner with one O(3)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra,  a cornercorner with one O(6)Na5Se octahedra,  a cornercorner with one O(7)Na5Se octahedra,  a cornercorner with one O(8)Na4Se trigonal bipyramid, corners with two equivalent O(5)Na4Se trigonal bipyramids, edges with two equivalent O(1)Na5Se octahedra, edges with two equivalent O(3)Na5Se octahedra, and edges with two equivalent O(7)Na5Se octahedra. The corner-sharing octahedral tilt angles range from 0-15°. In the fifth O site, O(5) is bonded to one Na(2), one Na(4), one Na(6), one Na(9), and one Se(1) atom to form distorted ONa4Se trigonal bipyramids that share  a cornercorner with one O(1)Na5Se octahedra, corners with two equivalent O(4)Na5Se octahedra,  a cornercorner with one O(5)Na4Se trigonal bipyramid, corners with three equivalent O(8)Na4Se trigonal bipyramids,  an edgeedge with one O(6)Na5Se octahedra, edges with two equivalent O(1)Na5Se octahedra, and edges with two equivalent O(7)Na5Se octahedra. The corner-sharing octahedral tilt angles range from 21-81°. In the sixth O site, O(6) is bonded to one Na(6), one Na(7), one Na(8), two equivalent Na(1), and one Se(1) atom to form distorted ONa5Se octahedra that share  a cornercorner with one O(1)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra, corners with two equivalent O(8)Na4Se trigonal bipyramids,  an edgeedge with one O(1)Na5Se octahedra,  an edgeedge with one O(6)Na5Se octahedra,  an edgeedge with one O(7)Na5Se octahedra, edges with two equivalent O(3)Na5Se octahedra,  an edgeedge with one O(5)Na4Se trigonal bipyramid, and  an edgeedge with one O(8)Na4Se trigonal bipyramid. The corner-sharing octahedral tilt angles range from 15-18°. In the seventh O site, O(7) is bonded to one Na(5), one Na(8), one Na(9), two equivalent Na(2), and one Se(1) atom to form ONa5Se octahedra that share  a cornercorner with one O(1)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra,  an edgeedge with one O(3)Na5Se octahedra,  an edgeedge with one O(6)Na5Se octahedra,  an edgeedge with one O(7)Na5Se octahedra, edges with two equivalent O(4)Na5Se octahedra, edges with three equivalent O(1)Na5Se octahedra, and edges with two equivalent O(5)Na4Se trigonal bipyramids. The corner-sharing octahedral tilt angles are 13°. In the eighth O site, O(8) is bonded to one Na(1), one Na(4), one Na(6), one Na(7), and one Se(2) atom to form distorted ONa4Se trigonal bipyramids that share  a cornercorner with one O(1)Na5Se octahedra,  a cornercorner with one O(3)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra, corners with two equivalent O(6)Na5Se octahedra,  a cornercorner with one O(8)Na4Se trigonal bipyramid, corners with three equivalent O(5)Na4Se trigonal bipyramids,  an edgeedge with one O(3)Na5Se octahedra, and  an edgeedge with one O(6)Na5Se octahedra. The corner-sharing octahedral tilt angles range from 19-85°. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Na(5), one Na(7), one Na(8), two equivalent Na(1), and one Se(1) atom. In the tenth O site, O(10) is bonded in a 6-coordinate geometry to one Na(3), one Na(7), one Na(9), two equivalent Na(5), and one Se(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.545
_cell_length_b   9.793
_cell_length_c   9.798
_cell_angle_alpha   113.326
_cell_angle_beta   96.317
_cell_angle_gamma   95.920
_symmetry_Int_Tables_number   1
_cell_volume   479.293
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Na  Na0  1  0.247  0.942  0.542  1.0
  Na  Na1  1  0.763  0.451  0.064  1.0
  Na  Na2  1  0.237  0.549  0.936  1.0
  Na  Na3  1  0.753  0.058  0.458  1.0
  Na  Na4  1  0.000  0.000  0.000  1.0
  Na  Na5  1  0.500  0.500  0.500  1.0
  Na  Na6  1  0.497  0.900  0.095  1.0
  Na  Na7  1  0.503  0.100  0.905  1.0
  Na  Na8  1  0.998  0.601  0.399  1.0
  Na  Na9  1  0.002  0.399  0.601  1.0
  Na  Na10  1  0.721  0.837  0.638  1.0
  Na  Na11  1  0.279  0.163  0.362  1.0
  Na  Na12  1  0.006  0.809  0.199  1.0
  Na  Na13  1  0.994  0.191  0.801  1.0
  Na  Na14  1  0.731  0.642  0.847  1.0
  Na  Na15  1  0.269  0.358  0.153  1.0
  Se  Se16  1  0.484  0.295  0.733  1.0
  Se  Se17  1  0.516  0.705  0.267  1.0
  Se  Se18  1  0.214  0.780  0.755  1.0
  Se  Se19  1  0.786  0.220  0.245  1.0
  O  O20  1  0.206  0.609  0.191  1.0
  O  O21  1  0.054  0.351  0.342  1.0
  O  O22  1  0.946  0.649  0.658  1.0
  O  O23  1  0.794  0.391  0.809  1.0
  O  O24  1  0.882  0.052  0.228  1.0
  O  O25  1  0.118  0.948  0.772  1.0
  O  O26  1  0.864  0.226  0.073  1.0
  O  O27  1  0.136  0.774  0.927  1.0
  O  O28  1  0.588  0.545  0.291  1.0
  O  O29  1  0.412  0.455  0.709  1.0
  O  O30  1  0.791  0.809  0.397  1.0
  O  O31  1  0.209  0.191  0.603  1.0
  O  O32  1  0.618  0.682  0.101  1.0
  O  O33  1  0.382  0.318  0.899  1.0
  O  O34  1  0.326  0.729  0.583  1.0
  O  O35  1  0.674  0.271  0.417  1.0
  O  O36  1  0.400  0.878  0.317  1.0
  O  O37  1  0.600  0.122  0.683  1.0
  O  O38  1  0.475  0.156  0.152  1.0
  O  O39  1  0.525  0.844  0.848  1.0
[/CIF]
.
The material structure described by Na4SeO5 crystallizes in the triclinic P-1 space group. There are nine inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(3), one O(8), two equivalent O(6), and two equivalent O(9) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Se(1)O5 trigonal bipyramids,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with three equivalent Na(7)O6 octahedra,  an edgeedge with one Se(2)O5 square pyramid, and  an edgeedge with one Se(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 11-33°. In the second Na site, Na(2) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(7) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(8)O6 octahedra,  a cornercorner with one Se(2)O5 square pyramid,  a cornercorner with one Se(1)O5 trigonal bipyramid,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with three equivalent Na(9)O6 octahedra, and edges with two equivalent Se(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 10-35°. In the third Na site, Na(3) is bonded to two equivalent O(10), two equivalent O(3), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Se(2)O5 square pyramids, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Na(9)O6 octahedra, edges with four equivalent Na(5)O6 octahedra, and edges with two equivalent Se(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 11-21°. In the fourth Na site, Na(4) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Se(2)O5 square pyramids, corners with two equivalent Se(1)O5 trigonal bipyramids, edges with two equivalent Na(7)O6 octahedra, edges with two equivalent Na(9)O6 octahedra, and edges with four equivalent Na(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-35°. In the fifth Na site, Na(5) is bonded to one O(3), one O(4), one O(7), one O(9), and two equivalent O(10) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(7)O6 octahedra, corners with two equivalent Na(9)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(8)O6 octahedra, edges with two equivalent Se(2)O5 square pyramids, and  an edgeedge with one Se(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 10-26°. In the sixth Na site, Na(6) is bonded to one O(1), one O(5), one O(6), one O(8), and two equivalent O(2) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(7)O6 octahedra, corners with two equivalent Na(9)O6 octahedra,  a cornercorner with one Se(2)O5 square pyramid,  a cornercorner with one Se(1)O5 trigonal bipyramid,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(4)O6 octahedra,  an edgeedge with one Se(2)O5 square pyramid, and  an edgeedge with one Se(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 24-34°. In the seventh Na site, Na(7) is bonded to one O(10), one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form distorted NaO6 octahedra that share  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(6)O6 octahedra, corners with two equivalent Se(1)O5 trigonal bipyramids,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with three equivalent Na(1)O6 octahedra, and edges with two equivalent Se(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 10-33°. In the eighth Na site, Na(8) is bonded to one O(1), one O(3), one O(4), one O(6), one O(7), and one O(9) atom to form distorted NaO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(7)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Se(2)O5 square pyramids,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, and edges with two equivalent Se(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 15-27°. In the ninth Na site, Na(9) is bonded to one O(1), one O(10), one O(2), one O(4), one O(5), and one O(7) atom to form distorted NaO6 octahedra that share  a cornercorner with one Na(8)O6 octahedra, corners with two equivalent Na(5)O6 octahedra, corners with two equivalent Na(6)O6 octahedra,  a cornercorner with one Se(2)O5 square pyramid,  a cornercorner with one Se(1)O5 trigonal bipyramid,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(7)O6 octahedra,  an edgeedge with one Na(8)O6 octahedra, edges with three equivalent Na(2)O6 octahedra,  an edgeedge with one Se(2)O5 square pyramid, and  an edgeedge with one Se(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 20-34°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(5), one O(6), one O(7), and one O(9) atom to form SeO5 trigonal bipyramids that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(7)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and edges with two equivalent Na(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-73°. In the second Se site, Se(2) is bonded to one O(10), one O(2), one O(3), one O(4), and one O(8) atom to form SeO5 square pyramids that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(6)O6 octahedra,  a cornercorner with one Na(9)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Na(8)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(6)O6 octahedra,  an edgeedge with one Na(9)O6 octahedra, edges with two equivalent Na(5)O6 octahedra, and edges with two equivalent Na(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-72°. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Na(6), one Na(8), one Na(9), two equivalent Na(2), and one Se(1) atom to form distorted ONa5Se octahedra that share  a cornercorner with one O(3)Na5Se octahedra,  a cornercorner with one O(6)Na5Se octahedra,  a cornercorner with one O(7)Na5Se octahedra,  a cornercorner with one O(5)Na4Se trigonal bipyramid,  a cornercorner with one O(8)Na4Se trigonal bipyramid,  an edgeedge with one O(1)Na5Se octahedra,  an edgeedge with one O(6)Na5Se octahedra, edges with two equivalent O(4)Na5Se octahedra, edges with three equivalent O(7)Na5Se octahedra, and edges with two equivalent O(5)Na4Se trigonal bipyramids. The corner-sharing octahedral tilt angles range from 12-18°. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Na(4), one Na(7), one Na(9), two equivalent Na(6), and one Se(2) atom. In the third O site, O(3) is bonded to one Na(1), one Na(3), one Na(5), one Na(7), one Na(8), and one Se(2) atom to form ONa5Se octahedra that share  a cornercorner with one O(1)Na5Se octahedra,  a cornercorner with one O(3)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra,  a cornercorner with one O(8)Na4Se trigonal bipyramid,  an edgeedge with one O(7)Na5Se octahedra, edges with two equivalent O(4)Na5Se octahedra, edges with two equivalent O(6)Na5Se octahedra, and  an edgeedge with one O(8)Na4Se trigonal bipyramid. The corner-sharing octahedral tilt angles range from 0-13°. In the fourth O site, O(4) is bonded to one Na(2), one Na(3), one Na(5), one Na(8), one Na(9), and one Se(2) atom to form distorted ONa5Se octahedra that share  a cornercorner with one O(3)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra,  a cornercorner with one O(6)Na5Se octahedra,  a cornercorner with one O(7)Na5Se octahedra,  a cornercorner with one O(8)Na4Se trigonal bipyramid, corners with two equivalent O(5)Na4Se trigonal bipyramids, edges with two equivalent O(1)Na5Se octahedra, edges with two equivalent O(3)Na5Se octahedra, and edges with two equivalent O(7)Na5Se octahedra. The corner-sharing octahedral tilt angles range from 0-15°. In the fifth O site, O(5) is bonded to one Na(2), one Na(4), one Na(6), one Na(9), and one Se(1) atom to form distorted ONa4Se trigonal bipyramids that share  a cornercorner with one O(1)Na5Se octahedra, corners with two equivalent O(4)Na5Se octahedra,  a cornercorner with one O(5)Na4Se trigonal bipyramid, corners with three equivalent O(8)Na4Se trigonal bipyramids,  an edgeedge with one O(6)Na5Se octahedra, edges with two equivalent O(1)Na5Se octahedra, and edges with two equivalent O(7)Na5Se octahedra. The corner-sharing octahedral tilt angles range from 21-81°. In the sixth O site, O(6) is bonded to one Na(6), one Na(7), one Na(8), two equivalent Na(1), and one Se(1) atom to form distorted ONa5Se octahedra that share  a cornercorner with one O(1)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra, corners with two equivalent O(8)Na4Se trigonal bipyramids,  an edgeedge with one O(1)Na5Se octahedra,  an edgeedge with one O(6)Na5Se octahedra,  an edgeedge with one O(7)Na5Se octahedra, edges with two equivalent O(3)Na5Se octahedra,  an edgeedge with one O(5)Na4Se trigonal bipyramid, and  an edgeedge with one O(8)Na4Se trigonal bipyramid. The corner-sharing octahedral tilt angles range from 15-18°. In the seventh O site, O(7) is bonded to one Na(5), one Na(8), one Na(9), two equivalent Na(2), and one Se(1) atom to form ONa5Se octahedra that share  a cornercorner with one O(1)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra,  an edgeedge with one O(3)Na5Se octahedra,  an edgeedge with one O(6)Na5Se octahedra,  an edgeedge with one O(7)Na5Se octahedra, edges with two equivalent O(4)Na5Se octahedra, edges with three equivalent O(1)Na5Se octahedra, and edges with two equivalent O(5)Na4Se trigonal bipyramids. The corner-sharing octahedral tilt angles are 13°. In the eighth O site, O(8) is bonded to one Na(1), one Na(4), one Na(6), one Na(7), and one Se(2) atom to form distorted ONa4Se trigonal bipyramids that share  a cornercorner with one O(1)Na5Se octahedra,  a cornercorner with one O(3)Na5Se octahedra,  a cornercorner with one O(4)Na5Se octahedra, corners with two equivalent O(6)Na5Se octahedra,  a cornercorner with one O(8)Na4Se trigonal bipyramid, corners with three equivalent O(5)Na4Se trigonal bipyramids,  an edgeedge with one O(3)Na5Se octahedra, and  an edgeedge with one O(6)Na5Se octahedra. The corner-sharing octahedral tilt angles range from 19-85°. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Na(5), one Na(7), one Na(8), two equivalent Na(1), and one Se(1) atom. In the tenth O site, O(10) is bonded in a 6-coordinate geometry to one Na(3), one Na(7), one Na(9), two equivalent Na(5), and one Se(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.545
_cell_length_b   9.793
_cell_length_c   9.798
_cell_angle_alpha   113.326
_cell_angle_beta   96.317
_cell_angle_gamma   95.920
_symmetry_Int_Tables_number   1
_cell_volume   479.293
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Na  Na0  1  0.247  0.942  0.542  1.0
  Na  Na1  1  0.763  0.451  0.064  1.0
  Na  Na2  1  0.237  0.549  0.936  1.0
  Na  Na3  1  0.753  0.058  0.458  1.0
  Na  Na4  1  0.000  0.000  0.000  1.0
  Na  Na5  1  0.500  0.500  0.500  1.0
  Na  Na6  1  0.497  0.900  0.095  1.0
  Na  Na7  1  0.503  0.100  0.905  1.0
  Na  Na8  1  0.998  0.601  0.399  1.0
  Na  Na9  1  0.002  0.399  0.601  1.0
  Na  Na10  1  0.721  0.837  0.638  1.0
  Na  Na11  1  0.279  0.163  0.362  1.0
  Na  Na12  1  0.006  0.809  0.199  1.0
  Na  Na13  1  0.994  0.191  0.801  1.0
  Na  Na14  1  0.731  0.642  0.847  1.0
  Na  Na15  1  0.269  0.358  0.153  1.0
  Se  Se16  1  0.484  0.295  0.733  1.0
  Se  Se17  1  0.516  0.705  0.267  1.0
  Se  Se18  1  0.214  0.780  0.755  1.0
  Se  Se19  1  0.786  0.220  0.245  1.0
  O  O20  1  0.206  0.609  0.191  1.0
  O  O21  1  0.054  0.351  0.342  1.0
  O  O22  1  0.946  0.649  0.658  1.0
  O  O23  1  0.794  0.391  0.809  1.0
  O  O24  1  0.882  0.052  0.228  1.0
  O  O25  1  0.118  0.948  0.772  1.0
  O  O26  1  0.864  0.226  0.073  1.0
  O  O27  1  0.136  0.774  0.927  1.0
  O  O28  1  0.588  0.545  0.291  1.0
  O  O29  1  0.412  0.455  0.709  1.0
  O  O30  1  0.791  0.809  0.397  1.0
  O  O31  1  0.209  0.191  0.603  1.0
  O  O32  1  0.618  0.682  0.101  1.0
  O  O33  1  0.382  0.318  0.899  1.0
  O  O34  1  0.326  0.729  0.583  1.0
  O  O35  1  0.674  0.271  0.417  1.0
  O  O36  1  0.400  0.878  0.317  1.0
  O  O37  1  0.600  0.122  0.683  1.0
  O  O38  1  0.475  0.156  0.152  1.0
  O  O39  1  0.525  0.844  0.848  1.0
[/CIF]
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