The material structure described by Na4NpO5 is Caswellsilverite-like structured and crystallizes in the tetragonal I4/m space group. Na(1) is bonded to one O(1) and five equivalent O(2) atoms to form NaO6 octahedra that share  a cornercorner with one Np(1)O6 octahedra, corners with five equivalent Na(1)O6 octahedra, edges with three equivalent Np(1)O6 octahedra, and edges with nine equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-18°. Np(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NpO6 octahedra that share corners with two equivalent Np(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, and edges with twelve equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Na(1) and two equivalent Np(1) atoms to form ONa4Np2 octahedra that share corners with two equivalent O(1)Na4Np2 octahedra, corners with four equivalent O(2)Na5Np octahedra, and edges with twelve equivalent O(2)Na5Np octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the second O site, O(2) is bonded to five equivalent Na(1) and one Np(1) atom to form distorted ONa5Np octahedra that share  a cornercorner with one O(1)Na4Np2 octahedra, corners with five equivalent O(2)Na5Np octahedra, edges with three equivalent O(1)Na4Np2 octahedra, and edges with nine equivalent O(2)Na5Np octahedra. The corner-sharing octahedral tilt angles range from 0-18°. is represented by the CIF card [CIF]
data_Na4NpO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.742
_cell_length_b   5.742
_cell_length_c   5.742
_cell_angle_alpha   99.230
_cell_angle_beta   99.230
_cell_angle_gamma   132.781
_symmetry_Int_Tables_number   1
_cell_volume   127.292
_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  0.804  0.403  0.206  1.0
  Na  Na1  1  0.403  0.196  0.599  1.0
  Na  Na2  1  0.597  0.804  0.401  1.0
  Na  Na3  1  0.196  0.597  0.794  1.0
  Np  Np4  1  0.000  0.000  0.000  1.0
  O  O5  1  0.500  0.500  0.000  1.0
  O  O6  1  0.743  0.079  0.822  1.0
  O  O7  1  0.079  0.257  0.336  1.0
  O  O8  1  0.921  0.743  0.664  1.0
  O  O9  1  0.257  0.921  0.178  1.0
[/CIF]
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The material structure described by Na4NpO5 is Caswellsilverite-like structured and crystallizes in the tetragonal I4/m space group. Na(1) is bonded to one O(1) and five equivalent O(2) atoms to form NaO6 octahedra that share  a cornercorner with one Np(1)O6 octahedra, corners with five equivalent Na(1)O6 octahedra, edges with three equivalent Np(1)O6 octahedra, and edges with nine equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-18°. Np(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form NpO6 octahedra that share corners with two equivalent Np(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra, and edges with twelve equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Na(1) and two equivalent Np(1) atoms to form ONa4Np2 octahedra that share corners with two equivalent O(1)Na4Np2 octahedra, corners with four equivalent O(2)Na5Np octahedra, and edges with twelve equivalent O(2)Na5Np octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the second O site, O(2) is bonded to five equivalent Na(1) and one Np(1) atom to form distorted ONa5Np octahedra that share  a cornercorner with one O(1)Na4Np2 octahedra, corners with five equivalent O(2)Na5Np octahedra, edges with three equivalent O(1)Na4Np2 octahedra, and edges with nine equivalent O(2)Na5Np octahedra. The corner-sharing octahedral tilt angles range from 0-18°. is represented by the CIF card [CIF]
data_Na4NpO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.742
_cell_length_b   5.742
_cell_length_c   5.742
_cell_angle_alpha   99.230
_cell_angle_beta   99.230
_cell_angle_gamma   132.781
_symmetry_Int_Tables_number   1
_cell_volume   127.292
_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  0.804  0.403  0.206  1.0
  Na  Na1  1  0.403  0.196  0.599  1.0
  Na  Na2  1  0.597  0.804  0.401  1.0
  Na  Na3  1  0.196  0.597  0.794  1.0
  Np  Np4  1  0.000  0.000  0.000  1.0
  O  O5  1  0.500  0.500  0.000  1.0
  O  O6  1  0.743  0.079  0.822  1.0
  O  O7  1  0.079  0.257  0.336  1.0
  O  O8  1  0.921  0.743  0.664  1.0
  O  O9  1  0.257  0.921  0.178  1.0
[/CIF]
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