The compound described by Na3Np is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Na(1) is bonded to eight equivalent Na(1) and four equivalent Np(1) atoms to form distorted NaNa8Np4 cuboctahedra that share corners with four equivalent Np(1)Na12 cuboctahedra, corners with fourteen equivalent Na(1)Na8Np4 cuboctahedra, edges with six equivalent Np(1)Na12 cuboctahedra, edges with twelve equivalent Na(1)Na8Np4 cuboctahedra, faces with four equivalent Np(1)Na12 cuboctahedra, and faces with sixteen equivalent Na(1)Na8Np4 cuboctahedra. Np(1) is bonded to twelve equivalent Na(1) atoms to form NpNa12 cuboctahedra that share corners with six equivalent Np(1)Na12 cuboctahedra, corners with twelve equivalent Na(1)Na8Np4 cuboctahedra, edges with eighteen equivalent Na(1)Na8Np4 cuboctahedra, faces with eight equivalent Np(1)Na12 cuboctahedra, and faces with twelve equivalent Na(1)Na8Np4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3Np
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.362
_cell_length_b   7.362
_cell_length_c   5.885
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   276.267
_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  0.160  0.320  0.250  1.0
  Na  Na1  1  0.680  0.840  0.250  1.0
  Na  Na2  1  0.160  0.840  0.250  1.0
  Na  Na3  1  0.840  0.680  0.750  1.0
  Na  Na4  1  0.320  0.160  0.750  1.0
  Na  Na5  1  0.840  0.160  0.750  1.0
  Np  Np6  1  0.333  0.667  0.750  1.0
  Np  Np7  1  0.667  0.333  0.250  1.0
[/CIF]
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The compound described by Na3Np is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Na(1) is bonded to eight equivalent Na(1) and four equivalent Np(1) atoms to form distorted NaNa8Np4 cuboctahedra that share corners with four equivalent Np(1)Na12 cuboctahedra, corners with fourteen equivalent Na(1)Na8Np4 cuboctahedra, edges with six equivalent Np(1)Na12 cuboctahedra, edges with twelve equivalent Na(1)Na8Np4 cuboctahedra, faces with four equivalent Np(1)Na12 cuboctahedra, and faces with sixteen equivalent Na(1)Na8Np4 cuboctahedra. Np(1) is bonded to twelve equivalent Na(1) atoms to form NpNa12 cuboctahedra that share corners with six equivalent Np(1)Na12 cuboctahedra, corners with twelve equivalent Na(1)Na8Np4 cuboctahedra, edges with eighteen equivalent Na(1)Na8Np4 cuboctahedra, faces with eight equivalent Np(1)Na12 cuboctahedra, and faces with twelve equivalent Na(1)Na8Np4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3Np
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.362
_cell_length_b   7.362
_cell_length_c   5.885
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   276.267
_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  0.160  0.320  0.250  1.0
  Na  Na1  1  0.680  0.840  0.250  1.0
  Na  Na2  1  0.160  0.840  0.250  1.0
  Na  Na3  1  0.840  0.680  0.750  1.0
  Na  Na4  1  0.320  0.160  0.750  1.0
  Na  Na5  1  0.840  0.160  0.750  1.0
  Np  Np6  1  0.333  0.667  0.750  1.0
  Np  Np7  1  0.667  0.333  0.250  1.0
[/CIF]
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