The compound described by Nb6CuSe8 crystallizes in the trigonal P-3 space group. Nb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. Cu(1) is bonded in a 6-coordinate geometry to six 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) and one Cu(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb6CuSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.056
_cell_length_b   10.056
_cell_length_c   3.476
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   304.419
_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
  Nb  Nb0  1  0.108  0.620  0.250  1.0
  Nb  Nb1  1  0.512  0.892  0.250  1.0
  Nb  Nb2  1  0.380  0.488  0.250  1.0
  Nb  Nb3  1  0.892  0.380  0.750  1.0
  Nb  Nb4  1  0.488  0.108  0.750  1.0
  Nb  Nb5  1  0.620  0.512  0.750  1.0
  Cu  Cu6  1  0.000  0.000  0.500  1.0
  Se  Se7  1  0.276  0.942  0.252  1.0
  Se  Se8  1  0.666  0.724  0.252  1.0
  Se  Se9  1  0.058  0.334  0.252  1.0
  Se  Se10  1  0.724  0.058  0.748  1.0
  Se  Se11  1  0.334  0.276  0.748  1.0
  Se  Se12  1  0.942  0.666  0.748  1.0
  Se  Se13  1  0.667  0.333  0.250  1.0
  Se  Se14  1  0.333  0.667  0.750  1.0
[/CIF]
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The compound described by Nb6CuSe8 crystallizes in the trigonal P-3 space group. Nb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. Cu(1) is bonded in a 6-coordinate geometry to six 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) and one Cu(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb6CuSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.056
_cell_length_b   10.056
_cell_length_c   3.476
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   304.419
_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
  Nb  Nb0  1  0.108  0.620  0.250  1.0
  Nb  Nb1  1  0.512  0.892  0.250  1.0
  Nb  Nb2  1  0.380  0.488  0.250  1.0
  Nb  Nb3  1  0.892  0.380  0.750  1.0
  Nb  Nb4  1  0.488  0.108  0.750  1.0
  Nb  Nb5  1  0.620  0.512  0.750  1.0
  Cu  Cu6  1  0.000  0.000  0.500  1.0
  Se  Se7  1  0.276  0.942  0.252  1.0
  Se  Se8  1  0.666  0.724  0.252  1.0
  Se  Se9  1  0.058  0.334  0.252  1.0
  Se  Se10  1  0.724  0.058  0.748  1.0
  Se  Se11  1  0.334  0.276  0.748  1.0
  Se  Se12  1  0.942  0.666  0.748  1.0
  Se  Se13  1  0.667  0.333  0.250  1.0
  Se  Se14  1  0.333  0.667  0.750  1.0
[/CIF]
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