The material described by Ni3Se is Uranium Silicide-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to eight Ni(1,1) and four equivalent Se(1) atoms to form distorted NiNi8Se4 cuboctahedra that share corners with four equivalent Se(1)Ni12 cuboctahedra; corners with fourteen equivalent Ni(1)Ni8Se4 cuboctahedra; edges with six equivalent Se(1)Ni12 cuboctahedra; edges with twelve Ni(1,1)Ni8Se4 cuboctahedra; faces with four equivalent Se(1)Ni12 cuboctahedra; and faces with sixteen Ni(1,1)Ni8Se4 cuboctahedra. In the second Ni site, Ni(1) is bonded to eight equivalent Ni(1) and four equivalent Se(1) atoms to form distorted NiNi8Se4 cuboctahedra that share corners with four equivalent Se(1)Ni12 cuboctahedra; corners with fourteen Ni(1,1)Ni8Se4 cuboctahedra; edges with six equivalent Se(1)Ni12 cuboctahedra; edges with twelve equivalent Ni(1)Ni8Se4 cuboctahedra; faces with four equivalent Se(1)Ni12 cuboctahedra; and faces with sixteen Ni(1,1)Ni8Se4 cuboctahedra. Se(1) is bonded to twelve Ni(1,1) atoms to form SeNi12 cuboctahedra that share corners with six equivalent Se(1)Ni12 cuboctahedra; corners with twelve Ni(1,1)Ni8Se4 cuboctahedra; edges with eighteen Ni(1,1)Ni8Se4 cuboctahedra; faces with eight equivalent Se(1)Ni12 cuboctahedra; and faces with twelve Ni(1,1)Ni8Se4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ni3Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.153
_cell_length_b   5.153
_cell_length_c   4.183
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   96.185
_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
  Ni  Ni0  1  0.164  0.328  0.250  1.0
  Ni  Ni1  1  0.672  0.836  0.250  1.0
  Ni  Ni2  1  0.164  0.836  0.250  1.0
  Ni  Ni3  1  0.836  0.672  0.750  1.0
  Ni  Ni4  1  0.328  0.164  0.750  1.0
  Ni  Ni5  1  0.836  0.164  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 material described by Ni3Se is Uranium Silicide-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to eight Ni(1,1) and four equivalent Se(1) atoms to form distorted NiNi8Se4 cuboctahedra that share corners with four equivalent Se(1)Ni12 cuboctahedra; corners with fourteen equivalent Ni(1)Ni8Se4 cuboctahedra; edges with six equivalent Se(1)Ni12 cuboctahedra; edges with twelve Ni(1,1)Ni8Se4 cuboctahedra; faces with four equivalent Se(1)Ni12 cuboctahedra; and faces with sixteen Ni(1,1)Ni8Se4 cuboctahedra. In the second Ni site, Ni(1) is bonded to eight equivalent Ni(1) and four equivalent Se(1) atoms to form distorted NiNi8Se4 cuboctahedra that share corners with four equivalent Se(1)Ni12 cuboctahedra; corners with fourteen Ni(1,1)Ni8Se4 cuboctahedra; edges with six equivalent Se(1)Ni12 cuboctahedra; edges with twelve equivalent Ni(1)Ni8Se4 cuboctahedra; faces with four equivalent Se(1)Ni12 cuboctahedra; and faces with sixteen Ni(1,1)Ni8Se4 cuboctahedra. Se(1) is bonded to twelve Ni(1,1) atoms to form SeNi12 cuboctahedra that share corners with six equivalent Se(1)Ni12 cuboctahedra; corners with twelve Ni(1,1)Ni8Se4 cuboctahedra; edges with eighteen Ni(1,1)Ni8Se4 cuboctahedra; faces with eight equivalent Se(1)Ni12 cuboctahedra; and faces with twelve Ni(1,1)Ni8Se4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ni3Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.153
_cell_length_b   5.153
_cell_length_c   4.183
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   96.185
_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
  Ni  Ni0  1  0.164  0.328  0.250  1.0
  Ni  Ni1  1  0.672  0.836  0.250  1.0
  Ni  Ni2  1  0.164  0.836  0.250  1.0
  Ni  Ni3  1  0.836  0.672  0.750  1.0
  Ni  Ni4  1  0.328  0.164  0.750  1.0
  Ni  Ni5  1  0.836  0.164  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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