The material structure described by NpCuSe2 crystallizes in the monoclinic P2_1/c space group. Np(1) is bonded in a 7-coordinate geometry to three equivalent Se(2) and four equivalent Se(1) atoms. Cu(1) is bonded in a 4-coordinate geometry to one Se(1) and three equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to four equivalent Np(1) and one Cu(1) atom to form a mixture of distorted corner and edge-sharing SeNp4Cu trigonal bipyramids. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to three equivalent Np(1) and three equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_NpCuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.356
_cell_length_b   6.601
_cell_length_c   7.094
_cell_angle_alpha   82.825
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   341.776
_cell_formula_units_Z   4
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
  Np  Np0  1  0.951  0.307  0.796  1.0
  Np  Np1  1  0.549  0.307  0.296  1.0
  Np  Np2  1  0.049  0.693  0.204  1.0
  Np  Np3  1  0.451  0.693  0.704  1.0
  Cu  Cu4  1  0.338  0.064  0.962  1.0
  Cu  Cu5  1  0.838  0.936  0.538  1.0
  Cu  Cu6  1  0.662  0.936  0.038  1.0
  Cu  Cu7  1  0.162  0.064  0.462  1.0
  Se  Se8  1  0.771  0.583  0.498  1.0
  Se  Se9  1  0.609  0.102  0.712  1.0
  Se  Se10  1  0.271  0.417  0.002  1.0
  Se  Se11  1  0.229  0.417  0.502  1.0
  Se  Se12  1  0.391  0.898  0.288  1.0
  Se  Se13  1  0.109  0.898  0.788  1.0
  Se  Se14  1  0.891  0.102  0.212  1.0
  Se  Se15  1  0.729  0.583  0.998  1.0
[/CIF]
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The material structure described by NpCuSe2 crystallizes in the monoclinic P2_1/c space group. Np(1) is bonded in a 7-coordinate geometry to three equivalent Se(2) and four equivalent Se(1) atoms. Cu(1) is bonded in a 4-coordinate geometry to one Se(1) and three equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to four equivalent Np(1) and one Cu(1) atom to form a mixture of distorted corner and edge-sharing SeNp4Cu trigonal bipyramids. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to three equivalent Np(1) and three equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_NpCuSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.356
_cell_length_b   6.601
_cell_length_c   7.094
_cell_angle_alpha   82.825
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   341.776
_cell_formula_units_Z   4
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
  Np  Np0  1  0.951  0.307  0.796  1.0
  Np  Np1  1  0.549  0.307  0.296  1.0
  Np  Np2  1  0.049  0.693  0.204  1.0
  Np  Np3  1  0.451  0.693  0.704  1.0
  Cu  Cu4  1  0.338  0.064  0.962  1.0
  Cu  Cu5  1  0.838  0.936  0.538  1.0
  Cu  Cu6  1  0.662  0.936  0.038  1.0
  Cu  Cu7  1  0.162  0.064  0.462  1.0
  Se  Se8  1  0.771  0.583  0.498  1.0
  Se  Se9  1  0.609  0.102  0.712  1.0
  Se  Se10  1  0.271  0.417  0.002  1.0
  Se  Se11  1  0.229  0.417  0.502  1.0
  Se  Se12  1  0.391  0.898  0.288  1.0
  Se  Se13  1  0.109  0.898  0.788  1.0
  Se  Se14  1  0.891  0.102  0.212  1.0
  Se  Se15  1  0.729  0.583  0.998  1.0
[/CIF]
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