The compound described by Ni3Bi2Se2 crystallizes in the monoclinic C2/m space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a distorted linear geometry to two equivalent Bi(1), two equivalent Bi(2), and two equivalent Se(1) atoms. In the second Ni site, Ni(2) is bonded in a distorted linear geometry to two equivalent Bi(1), two equivalent Bi(2), and two equivalent Se(1) atoms. In the third Ni site, Ni(3) is bonded in a distorted linear geometry to two equivalent Bi(1), two equivalent Bi(2), and two equivalent Se(1) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 6-coordinate geometry to two equivalent Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the second Bi site, Bi(2) is bonded in a 6-coordinate geometry to two equivalent Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. Se(1) is bonded in a distorted T-shaped geometry to one Ni(1), one Ni(2), and one Ni(3) atom. is represented by the CIF card [CIF]
data_Ni3(BiSe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.939
_cell_length_b   6.939
_cell_length_c   8.108
_cell_angle_alpha   56.594
_cell_angle_beta   56.594
_cell_angle_gamma   72.365
_symmetry_Int_Tables_number   1
_cell_volume   272.035
_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  0.278  0.722  0.500  1.0
  Ni  Ni1  1  0.722  0.278  0.500  1.0
  Ni  Ni2  1  0.981  0.981  0.794  1.0
  Ni  Ni3  1  0.019  0.019  0.206  1.0
  Ni  Ni4  1  0.000  0.500  0.500  1.0
  Ni  Ni5  1  0.500  0.000  0.500  1.0
  Bi  Bi6  1  0.790  0.790  0.691  1.0
  Bi  Bi7  1  0.210  0.210  0.309  1.0
  Bi  Bi8  1  0.749  0.749  0.260  1.0
  Bi  Bi9  1  0.251  0.251  0.740  1.0
  Se  Se10  1  0.255  0.695  0.805  1.0
  Se  Se11  1  0.305  0.745  0.195  1.0
  Se  Se12  1  0.745  0.305  0.195  1.0
  Se  Se13  1  0.695  0.255  0.805  1.0
[/CIF]
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The compound described by Ni3Bi2Se2 crystallizes in the monoclinic C2/m space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a distorted linear geometry to two equivalent Bi(1), two equivalent Bi(2), and two equivalent Se(1) atoms. In the second Ni site, Ni(2) is bonded in a distorted linear geometry to two equivalent Bi(1), two equivalent Bi(2), and two equivalent Se(1) atoms. In the third Ni site, Ni(3) is bonded in a distorted linear geometry to two equivalent Bi(1), two equivalent Bi(2), and two equivalent Se(1) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 6-coordinate geometry to two equivalent Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the second Bi site, Bi(2) is bonded in a 6-coordinate geometry to two equivalent Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. Se(1) is bonded in a distorted T-shaped geometry to one Ni(1), one Ni(2), and one Ni(3) atom. is represented by the CIF card [CIF]
data_Ni3(BiSe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.939
_cell_length_b   6.939
_cell_length_c   8.108
_cell_angle_alpha   56.594
_cell_angle_beta   56.594
_cell_angle_gamma   72.365
_symmetry_Int_Tables_number   1
_cell_volume   272.035
_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  0.278  0.722  0.500  1.0
  Ni  Ni1  1  0.722  0.278  0.500  1.0
  Ni  Ni2  1  0.981  0.981  0.794  1.0
  Ni  Ni3  1  0.019  0.019  0.206  1.0
  Ni  Ni4  1  0.000  0.500  0.500  1.0
  Ni  Ni5  1  0.500  0.000  0.500  1.0
  Bi  Bi6  1  0.790  0.790  0.691  1.0
  Bi  Bi7  1  0.210  0.210  0.309  1.0
  Bi  Bi8  1  0.749  0.749  0.260  1.0
  Bi  Bi9  1  0.251  0.251  0.740  1.0
  Se  Se10  1  0.255  0.695  0.805  1.0
  Se  Se11  1  0.305  0.745  0.195  1.0
  Se  Se12  1  0.745  0.305  0.195  1.0
  Se  Se13  1  0.695  0.255  0.805  1.0
[/CIF]
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