The crystal structure described by Na(Nb3Se4)2 crystallizes in the trigonal P-3 space group. Na(1) is bonded in a 6-coordinate geometry to six equivalent Se(1) atoms. Nb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded to six equivalent Nb(1) atoms to form distorted face-sharing SeNb6 pentagonal pyramids. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to one Na(1) and four equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Na(Nb3Se4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.094
_cell_length_b   10.094
_cell_length_c   3.526
_cell_angle_alpha   90.000
_cell_angle_beta   89.999
_cell_angle_gamma   120.001
_symmetry_Int_Tables_number   1
_cell_volume   311.130
_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  1.000  1.000  0.500  1.0
  Nb  Nb1  1  0.105  0.617  0.251  1.0
  Nb  Nb2  1  0.512  0.895  0.251  1.0
  Nb  Nb3  1  0.383  0.488  0.251  1.0
  Nb  Nb4  1  0.895  0.383  0.749  1.0
  Nb  Nb5  1  0.488  0.105  0.749  1.0
  Nb  Nb6  1  0.617  0.512  0.749  1.0
  Se  Se7  1  0.279  0.942  0.249  1.0
  Se  Se8  1  0.663  0.721  0.248  1.0
  Se  Se9  1  0.058  0.337  0.249  1.0
  Se  Se10  1  0.721  0.058  0.752  1.0
  Se  Se11  1  0.337  0.279  0.751  1.0
  Se  Se12  1  0.942  0.663  0.752  1.0
  Se  Se13  1  0.667  0.333  0.249  1.0
  Se  Se14  1  0.333  0.667  0.751  1.0
[/CIF]
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The crystal structure described by Na(Nb3Se4)2 crystallizes in the trigonal P-3 space group. Na(1) is bonded in a 6-coordinate geometry to six equivalent Se(1) atoms. Nb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded to six equivalent Nb(1) atoms to form distorted face-sharing SeNb6 pentagonal pyramids. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to one Na(1) and four equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Na(Nb3Se4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.094
_cell_length_b   10.094
_cell_length_c   3.526
_cell_angle_alpha   90.000
_cell_angle_beta   89.999
_cell_angle_gamma   120.001
_symmetry_Int_Tables_number   1
_cell_volume   311.130
_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  1.000  1.000  0.500  1.0
  Nb  Nb1  1  0.105  0.617  0.251  1.0
  Nb  Nb2  1  0.512  0.895  0.251  1.0
  Nb  Nb3  1  0.383  0.488  0.251  1.0
  Nb  Nb4  1  0.895  0.383  0.749  1.0
  Nb  Nb5  1  0.488  0.105  0.749  1.0
  Nb  Nb6  1  0.617  0.512  0.749  1.0
  Se  Se7  1  0.279  0.942  0.249  1.0
  Se  Se8  1  0.663  0.721  0.248  1.0
  Se  Se9  1  0.058  0.337  0.249  1.0
  Se  Se10  1  0.721  0.058  0.752  1.0
  Se  Se11  1  0.337  0.279  0.751  1.0
  Se  Se12  1  0.942  0.663  0.752  1.0
  Se  Se13  1  0.667  0.333  0.249  1.0
  Se  Se14  1  0.333  0.667  0.751  1.0
[/CIF]
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