The structure described by Na5NpO6 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Na(3)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with three equivalent Na(1)O6 octahedra, edges with three equivalent Np(1)O6 octahedra, and edges with four equivalent Na(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-17°. In the second Na site, Na(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NaO6 octahedra that share corners with two equivalent Np(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Np(1)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with six equivalent Na(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the third Na site, Na(3) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NaO6 octahedra that share corners with two equivalent Np(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Np(1)O6 octahedra, edges with three equivalent Na(2)O6 octahedra, edges with three equivalent Na(3)O6 octahedra, and edges with four equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-17°. Np(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NpO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Na(3)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with four equivalent Na(3)O6 octahedra, and edges with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), two equivalent Na(1), two equivalent Na(3), and one Np(1) atom to form a mixture of corner and edge-sharing ONa5Np octahedra. The corner-sharing octahedral tilt angles range from 0-15°. In the second O site, O(2) is bonded to one Na(2), two equivalent Na(1), two equivalent Na(3), and one Np(1) atom to form a mixture of distorted corner and edge-sharing ONa5Np octahedra. The corner-sharing octahedral tilt angles range from 0-11°. is represented by the CIF file [CIF]
data_Na5NpO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.732
_cell_length_b   5.732
_cell_length_c   5.697
_cell_angle_alpha   79.970
_cell_angle_beta   79.970
_cell_angle_gamma   119.655
_symmetry_Int_Tables_number   1
_cell_volume   152.614
_cell_formula_units_Z   1
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  0.333  0.667  0.000  1.0
  Na  Na1  1  0.667  0.333  0.000  1.0
  Na  Na2  1  0.500  0.500  0.500  1.0
  Na  Na3  1  0.177  0.823  0.500  1.0
  Na  Na4  1  0.823  0.177  0.500  1.0
  Np  Np5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.926  0.636  0.224  1.0
  O  O7  1  0.636  0.926  0.224  1.0
  O  O8  1  0.074  0.364  0.776  1.0
  O  O9  1  0.364  0.074  0.776  1.0
  O  O10  1  0.788  0.788  0.787  1.0
  O  O11  1  0.212  0.212  0.213  1.0
[/CIF]
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The structure described by Na5NpO6 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Na(3)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with three equivalent Na(1)O6 octahedra, edges with three equivalent Np(1)O6 octahedra, and edges with four equivalent Na(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-17°. In the second Na site, Na(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NaO6 octahedra that share corners with two equivalent Np(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Np(1)O6 octahedra, edges with four equivalent Na(1)O6 octahedra, and edges with six equivalent Na(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the third Na site, Na(3) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NaO6 octahedra that share corners with two equivalent Np(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, edges with two equivalent Np(1)O6 octahedra, edges with three equivalent Na(2)O6 octahedra, edges with three equivalent Na(3)O6 octahedra, and edges with four equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-17°. Np(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NpO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with four equivalent Na(3)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with four equivalent Na(3)O6 octahedra, and edges with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), two equivalent Na(1), two equivalent Na(3), and one Np(1) atom to form a mixture of corner and edge-sharing ONa5Np octahedra. The corner-sharing octahedral tilt angles range from 0-15°. In the second O site, O(2) is bonded to one Na(2), two equivalent Na(1), two equivalent Na(3), and one Np(1) atom to form a mixture of distorted corner and edge-sharing ONa5Np octahedra. The corner-sharing octahedral tilt angles range from 0-11°. is represented by the CIF file [CIF]
data_Na5NpO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.732
_cell_length_b   5.732
_cell_length_c   5.697
_cell_angle_alpha   79.970
_cell_angle_beta   79.970
_cell_angle_gamma   119.655
_symmetry_Int_Tables_number   1
_cell_volume   152.614
_cell_formula_units_Z   1
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  0.333  0.667  0.000  1.0
  Na  Na1  1  0.667  0.333  0.000  1.0
  Na  Na2  1  0.500  0.500  0.500  1.0
  Na  Na3  1  0.177  0.823  0.500  1.0
  Na  Na4  1  0.823  0.177  0.500  1.0
  Np  Np5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.926  0.636  0.224  1.0
  O  O7  1  0.636  0.926  0.224  1.0
  O  O8  1  0.074  0.364  0.776  1.0
  O  O9  1  0.364  0.074  0.776  1.0
  O  O10  1  0.788  0.788  0.787  1.0
  O  O11  1  0.212  0.212  0.213  1.0
[/CIF]
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