The material described by Na2OsO8 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form distorted NaO4 trigonal pyramids that share  a cornercorner with one Na(2)O5 trigonal bipyramid, corners with three equivalent Os(1)O5 trigonal bipyramids, and  an edgeedge with one Na(2)O5 trigonal bipyramid. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(6) atom to form NaO5 trigonal bipyramids that share corners with three equivalent Os(1)O5 trigonal bipyramids,  a cornercorner with one Na(1)O4 trigonal pyramid, and  an edgeedge with one Na(1)O4 trigonal pyramid. Os(1) is bonded to one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form OsO5 trigonal bipyramids that share corners with three equivalent Na(2)O5 trigonal bipyramids and corners with three equivalent Na(1)O4 trigonal pyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Na(2) and one O(7) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one Na(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Na(2) and one Os(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Na(1) and one Os(1) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Na(1), one Na(2), and one Os(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Na(1), one Na(2), and one Os(1) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one O(1) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one Os(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2OsO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.155
_cell_length_b   5.672
_cell_length_c   6.358
_cell_angle_alpha   86.175
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   365.440
_cell_formula_units_Z   2
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  0.397  0.193  0.312  1.0
  Na  Na1  1  0.897  0.807  0.688  1.0
  Na  Na2  1  0.418  0.795  0.744  1.0
  Na  Na3  1  0.918  0.205  0.256  1.0
  Os  Os4  1  0.172  0.734  0.294  1.0
  Os  Os5  1  0.672  0.266  0.706  1.0
  O  O6  1  0.776  0.617  0.153  1.0
  O  O7  1  0.276  0.383  0.847  1.0
  O  O8  1  0.427  0.863  0.103  1.0
  O  O9  1  0.927  0.137  0.897  1.0
  O  O10  1  0.113  0.438  0.301  1.0
  O  O11  1  0.613  0.562  0.699  1.0
  O  O12  1  0.339  0.590  0.259  1.0
  O  O13  1  0.839  0.410  0.741  1.0
  O  O14  1  0.249  0.893  0.495  1.0
  O  O15  1  0.749  0.107  0.505  1.0
  O  O16  1  0.010  0.837  0.368  1.0
  O  O17  1  0.510  0.163  0.632  1.0
  O  O18  1  0.162  0.423  0.782  1.0
  O  O19  1  0.662  0.577  0.218  1.0
  O  O20  1  0.180  0.884  0.044  1.0
  O  O21  1  0.680  0.116  0.956  1.0
[/CIF]
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The material described by Na2OsO8 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form distorted NaO4 trigonal pyramids that share  a cornercorner with one Na(2)O5 trigonal bipyramid, corners with three equivalent Os(1)O5 trigonal bipyramids, and  an edgeedge with one Na(2)O5 trigonal bipyramid. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(6) atom to form NaO5 trigonal bipyramids that share corners with three equivalent Os(1)O5 trigonal bipyramids,  a cornercorner with one Na(1)O4 trigonal pyramid, and  an edgeedge with one Na(1)O4 trigonal pyramid. Os(1) is bonded to one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form OsO5 trigonal bipyramids that share corners with three equivalent Na(2)O5 trigonal bipyramids and corners with three equivalent Na(1)O4 trigonal pyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one Na(2) and one O(7) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Na(1) and one Na(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Na(2) and one Os(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Na(1) and one Os(1) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Na(1), one Na(2), and one Os(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Na(1), one Na(2), and one Os(1) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one O(1) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one Os(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2OsO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.155
_cell_length_b   5.672
_cell_length_c   6.358
_cell_angle_alpha   86.175
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   365.440
_cell_formula_units_Z   2
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  0.397  0.193  0.312  1.0
  Na  Na1  1  0.897  0.807  0.688  1.0
  Na  Na2  1  0.418  0.795  0.744  1.0
  Na  Na3  1  0.918  0.205  0.256  1.0
  Os  Os4  1  0.172  0.734  0.294  1.0
  Os  Os5  1  0.672  0.266  0.706  1.0
  O  O6  1  0.776  0.617  0.153  1.0
  O  O7  1  0.276  0.383  0.847  1.0
  O  O8  1  0.427  0.863  0.103  1.0
  O  O9  1  0.927  0.137  0.897  1.0
  O  O10  1  0.113  0.438  0.301  1.0
  O  O11  1  0.613  0.562  0.699  1.0
  O  O12  1  0.339  0.590  0.259  1.0
  O  O13  1  0.839  0.410  0.741  1.0
  O  O14  1  0.249  0.893  0.495  1.0
  O  O15  1  0.749  0.107  0.505  1.0
  O  O16  1  0.010  0.837  0.368  1.0
  O  O17  1  0.510  0.163  0.632  1.0
  O  O18  1  0.162  0.423  0.782  1.0
  O  O19  1  0.662  0.577  0.218  1.0
  O  O20  1  0.180  0.884  0.044  1.0
  O  O21  1  0.680  0.116  0.956  1.0
[/CIF]
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