The crystal structure described by NaNpSeO6 crystallizes in the monoclinic C2/m space group. Na(1) is bonded to one O(3), two equivalent O(4), and two equivalent O(5) atoms to form distorted NaO5 square pyramids that share  a cornercorner with one Np(1)O7 pentagonal bipyramid,  an edgeedge with one Np(1)O7 pentagonal bipyramid, and edges with two equivalent Na(1)O5 square pyramids. Np(1) is bonded to one O(2), one O(3), one O(4), and four equivalent O(1) atoms to form distorted NpO7 pentagonal bipyramids that share  a cornercorner with one Na(1)O5 square pyramid, edges with two equivalent Np(1)O7 pentagonal bipyramids, and  an edgeedge with one Na(1)O5 square pyramid. Se(1) is bonded in a trigonal non-coplanar geometry to one O(3) and two equivalent O(1) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Np(1) and one Se(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Np(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Na(1), one Np(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one Np(1) atom. In the fifth O site, O(5) is bonded in a water-like geometry to two equivalent Na(1) atoms. is represented by the CIF card [CIF]
data_NaNpSeO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.417
_cell_length_b   8.417
_cell_length_c   6.842
_cell_angle_alpha   70.391
_cell_angle_beta   109.609
_cell_angle_gamma   128.814
_symmetry_Int_Tables_number   1
_cell_volume   350.574
_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  0.537  0.463  0.791  1.0
  Na  Na1  1  0.463  0.537  0.209  1.0
  Np  Np2  1  0.737  0.263  0.631  1.0
  Np  Np3  1  0.263  0.737  0.369  1.0
  Se  Se4  1  0.203  0.797  0.800  1.0
  Se  Se5  1  0.797  0.203  0.200  1.0
  O  O6  1  0.068  0.585  0.675  1.0
  O  O7  1  0.415  0.932  0.675  1.0
  O  O8  1  0.932  0.415  0.325  1.0
  O  O9  1  0.585  0.068  0.325  1.0
  O  O10  1  0.863  0.137  0.765  1.0
  O  O11  1  0.137  0.863  0.235  1.0
  O  O12  1  0.711  0.289  0.950  1.0
  O  O13  1  0.289  0.711  0.050  1.0
  O  O14  1  0.608  0.392  0.509  1.0
  O  O15  1  0.392  0.608  0.491  1.0
  O  O16  1  0.293  0.293  0.000  1.0
  O  O17  1  0.707  0.707  0.000  1.0
[/CIF]
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The crystal structure described by NaNpSeO6 crystallizes in the monoclinic C2/m space group. Na(1) is bonded to one O(3), two equivalent O(4), and two equivalent O(5) atoms to form distorted NaO5 square pyramids that share  a cornercorner with one Np(1)O7 pentagonal bipyramid,  an edgeedge with one Np(1)O7 pentagonal bipyramid, and edges with two equivalent Na(1)O5 square pyramids. Np(1) is bonded to one O(2), one O(3), one O(4), and four equivalent O(1) atoms to form distorted NpO7 pentagonal bipyramids that share  a cornercorner with one Na(1)O5 square pyramid, edges with two equivalent Np(1)O7 pentagonal bipyramids, and  an edgeedge with one Na(1)O5 square pyramid. Se(1) is bonded in a trigonal non-coplanar geometry to one O(3) and two equivalent O(1) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Np(1) and one Se(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Np(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Na(1), one Np(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Na(1) and one Np(1) atom. In the fifth O site, O(5) is bonded in a water-like geometry to two equivalent Na(1) atoms. is represented by the CIF card [CIF]
data_NaNpSeO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.417
_cell_length_b   8.417
_cell_length_c   6.842
_cell_angle_alpha   70.391
_cell_angle_beta   109.609
_cell_angle_gamma   128.814
_symmetry_Int_Tables_number   1
_cell_volume   350.574
_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  0.537  0.463  0.791  1.0
  Na  Na1  1  0.463  0.537  0.209  1.0
  Np  Np2  1  0.737  0.263  0.631  1.0
  Np  Np3  1  0.263  0.737  0.369  1.0
  Se  Se4  1  0.203  0.797  0.800  1.0
  Se  Se5  1  0.797  0.203  0.200  1.0
  O  O6  1  0.068  0.585  0.675  1.0
  O  O7  1  0.415  0.932  0.675  1.0
  O  O8  1  0.932  0.415  0.325  1.0
  O  O9  1  0.585  0.068  0.325  1.0
  O  O10  1  0.863  0.137  0.765  1.0
  O  O11  1  0.137  0.863  0.235  1.0
  O  O12  1  0.711  0.289  0.950  1.0
  O  O13  1  0.289  0.711  0.050  1.0
  O  O14  1  0.608  0.392  0.509  1.0
  O  O15  1  0.392  0.608  0.491  1.0
  O  O16  1  0.293  0.293  0.000  1.0
  O  O17  1  0.707  0.707  0.000  1.0
[/CIF]
.