The structure described by Nb3Se4 crystallizes in the hexagonal P6_3/m space group. 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 4-coordinate geometry to four equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Nb3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.157
_cell_length_b   10.157
_cell_length_c   3.490
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   311.811
_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
  Nb  Nb0  1  0.513  0.894  0.750  1.0
  Nb  Nb1  1  0.619  0.513  0.250  1.0
  Nb  Nb2  1  0.894  0.381  0.250  1.0
  Nb  Nb3  1  0.106  0.619  0.750  1.0
  Nb  Nb4  1  0.381  0.487  0.750  1.0
  Nb  Nb5  1  0.487  0.106  0.250  1.0
  Se  Se6  1  0.659  0.719  0.750  1.0
  Se  Se7  1  0.940  0.659  0.250  1.0
  Se  Se8  1  0.719  0.060  0.250  1.0
  Se  Se9  1  0.281  0.940  0.750  1.0
  Se  Se10  1  0.060  0.341  0.750  1.0
  Se  Se11  1  0.341  0.281  0.250  1.0
  Se  Se12  1  0.667  0.333  0.750  1.0
  Se  Se13  1  0.333  0.667  0.250  1.0
[/CIF]
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The structure described by Nb3Se4 crystallizes in the hexagonal P6_3/m space group. 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 4-coordinate geometry to four equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Nb3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.157
_cell_length_b   10.157
_cell_length_c   3.490
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   311.811
_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
  Nb  Nb0  1  0.513  0.894  0.750  1.0
  Nb  Nb1  1  0.619  0.513  0.250  1.0
  Nb  Nb2  1  0.894  0.381  0.250  1.0
  Nb  Nb3  1  0.106  0.619  0.750  1.0
  Nb  Nb4  1  0.381  0.487  0.750  1.0
  Nb  Nb5  1  0.487  0.106  0.250  1.0
  Se  Se6  1  0.659  0.719  0.750  1.0
  Se  Se7  1  0.940  0.659  0.250  1.0
  Se  Se8  1  0.719  0.060  0.250  1.0
  Se  Se9  1  0.281  0.940  0.750  1.0
  Se  Se10  1  0.060  0.341  0.750  1.0
  Se  Se11  1  0.341  0.281  0.250  1.0
  Se  Se12  1  0.667  0.333  0.750  1.0
  Se  Se13  1  0.333  0.667  0.250  1.0
[/CIF]
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