The compound described by Nb3Se is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to eight Nb(1,1,1) and four equivalent Se(1) atoms to form distorted NbNb8Se4 cuboctahedra that share corners with four equivalent Se(1)Nb12 cuboctahedra; corners with fourteen Nb(1,1)Nb8Se4 cuboctahedra; edges with six equivalent Se(1)Nb12 cuboctahedra; edges with twelve Nb(1,1,1)Nb8Se4 cuboctahedra; faces with four equivalent Se(1)Nb12 cuboctahedra; and faces with sixteen Nb(1,1,1)Nb8Se4 cuboctahedra. In the second Nb site, Nb(1) is bonded to eight equivalent Nb(1) and four equivalent Se(1) atoms to form distorted NbNb8Se4 cuboctahedra that share corners with four equivalent Se(1)Nb12 cuboctahedra; corners with fourteen Nb(1,1)Nb8Se4 cuboctahedra; edges with six equivalent Se(1)Nb12 cuboctahedra; edges with twelve equivalent Nb(1)Nb8Se4 cuboctahedra; faces with four equivalent Se(1)Nb12 cuboctahedra; and faces with sixteen Nb(1,1,1)Nb8Se4 cuboctahedra. In the third Nb site, Nb(1) is bonded to eight equivalent Nb(1) and four equivalent Se(1) atoms to form distorted NbNb8Se4 cuboctahedra that share corners with four equivalent Se(1)Nb12 cuboctahedra; corners with fourteen Nb(1,1)Nb8Se4 cuboctahedra; edges with six equivalent Se(1)Nb12 cuboctahedra; edges with twelve equivalent Nb(1)Nb8Se4 cuboctahedra; faces with four equivalent Se(1)Nb12 cuboctahedra; and faces with sixteen Nb(1,1,1)Nb8Se4 cuboctahedra. Se(1) is bonded to twelve Nb(1,1,1) atoms to form SeNb12 cuboctahedra that share corners with six equivalent Se(1)Nb12 cuboctahedra; corners with twelve Nb(1,1)Nb8Se4 cuboctahedra; edges with eighteen Nb(1,1,1)Nb8Se4 cuboctahedra; faces with eight equivalent Se(1)Nb12 cuboctahedra; and faces with twelve Nb(1,1,1)Nb8Se4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb3Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.767
_cell_length_b   5.767
_cell_length_c   4.925
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   141.867
_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  0.161  0.321  0.250  1.0
  Nb  Nb1  1  0.679  0.839  0.250  1.0
  Nb  Nb2  1  0.161  0.839  0.250  1.0
  Nb  Nb3  1  0.839  0.679  0.750  1.0
  Nb  Nb4  1  0.321  0.161  0.750  1.0
  Nb  Nb5  1  0.839  0.161  0.750  1.0
  Se  Se6  1  0.333  0.667  0.750  1.0
  Se  Se7  1  0.667  0.333  0.250  1.0
[/CIF]
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The compound described by Nb3Se is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to eight Nb(1,1,1) and four equivalent Se(1) atoms to form distorted NbNb8Se4 cuboctahedra that share corners with four equivalent Se(1)Nb12 cuboctahedra; corners with fourteen Nb(1,1)Nb8Se4 cuboctahedra; edges with six equivalent Se(1)Nb12 cuboctahedra; edges with twelve Nb(1,1,1)Nb8Se4 cuboctahedra; faces with four equivalent Se(1)Nb12 cuboctahedra; and faces with sixteen Nb(1,1,1)Nb8Se4 cuboctahedra. In the second Nb site, Nb(1) is bonded to eight equivalent Nb(1) and four equivalent Se(1) atoms to form distorted NbNb8Se4 cuboctahedra that share corners with four equivalent Se(1)Nb12 cuboctahedra; corners with fourteen Nb(1,1)Nb8Se4 cuboctahedra; edges with six equivalent Se(1)Nb12 cuboctahedra; edges with twelve equivalent Nb(1)Nb8Se4 cuboctahedra; faces with four equivalent Se(1)Nb12 cuboctahedra; and faces with sixteen Nb(1,1,1)Nb8Se4 cuboctahedra. In the third Nb site, Nb(1) is bonded to eight equivalent Nb(1) and four equivalent Se(1) atoms to form distorted NbNb8Se4 cuboctahedra that share corners with four equivalent Se(1)Nb12 cuboctahedra; corners with fourteen Nb(1,1)Nb8Se4 cuboctahedra; edges with six equivalent Se(1)Nb12 cuboctahedra; edges with twelve equivalent Nb(1)Nb8Se4 cuboctahedra; faces with four equivalent Se(1)Nb12 cuboctahedra; and faces with sixteen Nb(1,1,1)Nb8Se4 cuboctahedra. Se(1) is bonded to twelve Nb(1,1,1) atoms to form SeNb12 cuboctahedra that share corners with six equivalent Se(1)Nb12 cuboctahedra; corners with twelve Nb(1,1)Nb8Se4 cuboctahedra; edges with eighteen Nb(1,1,1)Nb8Se4 cuboctahedra; faces with eight equivalent Se(1)Nb12 cuboctahedra; and faces with twelve Nb(1,1,1)Nb8Se4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb3Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.767
_cell_length_b   5.767
_cell_length_c   4.925
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   141.867
_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  0.161  0.321  0.250  1.0
  Nb  Nb1  1  0.679  0.839  0.250  1.0
  Nb  Nb2  1  0.161  0.839  0.250  1.0
  Nb  Nb3  1  0.839  0.679  0.750  1.0
  Nb  Nb4  1  0.321  0.161  0.750  1.0
  Nb  Nb5  1  0.839  0.161  0.750  1.0
  Se  Se6  1  0.333  0.667  0.750  1.0
  Se  Se7  1  0.667  0.333  0.250  1.0
[/CIF]
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