The crystal structure described by Pu3Np is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Pu sites. In the first Pu site, Pu(1) is bonded to four equivalent Pu(1), four equivalent Pu(2), and four equivalent Np(1) atoms to form PuPu8Np4 cuboctahedra that share corners with twelve equivalent Pu(1)Pu8Np4 cuboctahedra, edges with eight equivalent Pu(1)Pu8Np4 cuboctahedra, edges with eight equivalent Pu(2)Pu8Np4 cuboctahedra, edges with eight equivalent Np(1)Pu12 cuboctahedra, faces with four equivalent Pu(2)Pu8Np4 cuboctahedra, faces with four equivalent Np(1)Pu12 cuboctahedra, and faces with ten equivalent Pu(1)Pu8Np4 cuboctahedra. In the second Pu site, Pu(2) is bonded to eight equivalent Pu(1) and four equivalent Np(1) atoms to form PuPu8Np4 cuboctahedra that share corners with four equivalent Pu(2)Pu8Np4 cuboctahedra, corners with eight equivalent Np(1)Pu12 cuboctahedra, edges with eight equivalent Pu(2)Pu8Np4 cuboctahedra, edges with sixteen equivalent Pu(1)Pu8Np4 cuboctahedra, faces with four equivalent Pu(2)Pu8Np4 cuboctahedra, faces with six equivalent Np(1)Pu12 cuboctahedra, and faces with eight equivalent Pu(1)Pu8Np4 cuboctahedra. Np(1) is bonded to four equivalent Pu(2) and eight equivalent Pu(1) atoms to form NpPu12 cuboctahedra that share corners with four equivalent Np(1)Pu12 cuboctahedra, corners with eight equivalent Pu(2)Pu8Np4 cuboctahedra, edges with eight equivalent Np(1)Pu12 cuboctahedra, edges with sixteen equivalent Pu(1)Pu8Np4 cuboctahedra, faces with four equivalent Np(1)Pu12 cuboctahedra, faces with six equivalent Pu(2)Pu8Np4 cuboctahedra, and faces with eight equivalent Pu(1)Pu8Np4 cuboctahedra. is represented by the CIF file [CIF]
data_Pu3Np
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.497
_cell_length_b   5.497
_cell_length_c   5.497
_cell_angle_alpha   131.430
_cell_angle_beta   131.430
_cell_angle_gamma   71.131
_symmetry_Int_Tables_number   1
_cell_volume   91.422
_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
  Pu  Pu0  1  0.750  0.250  0.500  1.0
  Pu  Pu1  1  0.250  0.750  0.500  1.0
  Pu  Pu2  1  0.500  0.500  0.000  1.0
  Np  Np3  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Pu3Np is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Pu sites. In the first Pu site, Pu(1) is bonded to four equivalent Pu(1), four equivalent Pu(2), and four equivalent Np(1) atoms to form PuPu8Np4 cuboctahedra that share corners with twelve equivalent Pu(1)Pu8Np4 cuboctahedra, edges with eight equivalent Pu(1)Pu8Np4 cuboctahedra, edges with eight equivalent Pu(2)Pu8Np4 cuboctahedra, edges with eight equivalent Np(1)Pu12 cuboctahedra, faces with four equivalent Pu(2)Pu8Np4 cuboctahedra, faces with four equivalent Np(1)Pu12 cuboctahedra, and faces with ten equivalent Pu(1)Pu8Np4 cuboctahedra. In the second Pu site, Pu(2) is bonded to eight equivalent Pu(1) and four equivalent Np(1) atoms to form PuPu8Np4 cuboctahedra that share corners with four equivalent Pu(2)Pu8Np4 cuboctahedra, corners with eight equivalent Np(1)Pu12 cuboctahedra, edges with eight equivalent Pu(2)Pu8Np4 cuboctahedra, edges with sixteen equivalent Pu(1)Pu8Np4 cuboctahedra, faces with four equivalent Pu(2)Pu8Np4 cuboctahedra, faces with six equivalent Np(1)Pu12 cuboctahedra, and faces with eight equivalent Pu(1)Pu8Np4 cuboctahedra. Np(1) is bonded to four equivalent Pu(2) and eight equivalent Pu(1) atoms to form NpPu12 cuboctahedra that share corners with four equivalent Np(1)Pu12 cuboctahedra, corners with eight equivalent Pu(2)Pu8Np4 cuboctahedra, edges with eight equivalent Np(1)Pu12 cuboctahedra, edges with sixteen equivalent Pu(1)Pu8Np4 cuboctahedra, faces with four equivalent Np(1)Pu12 cuboctahedra, faces with six equivalent Pu(2)Pu8Np4 cuboctahedra, and faces with eight equivalent Pu(1)Pu8Np4 cuboctahedra. is represented by the CIF file [CIF]
data_Pu3Np
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.497
_cell_length_b   5.497
_cell_length_c   5.497
_cell_angle_alpha   131.430
_cell_angle_beta   131.430
_cell_angle_gamma   71.131
_symmetry_Int_Tables_number   1
_cell_volume   91.422
_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
  Pu  Pu0  1  0.750  0.250  0.500  1.0
  Pu  Pu1  1  0.250  0.750  0.500  1.0
  Pu  Pu2  1  0.500  0.500  0.000  1.0
  Np  Np3  1  0.000  0.000  0.000  1.0
[/CIF]
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