The compound described by Ni6Se5 crystallizes in the orthorhombic Cmc2_1 space group. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 5-coordinate geometry to one Se(5), two equivalent Se(1), and two equivalent Se(2) atoms. In the second Ni site, Ni(2) is bonded in a 5-coordinate geometry to one Se(3), two equivalent Se(2), and two equivalent Se(5) atoms. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one Se(4), two equivalent Se(1), and two equivalent Se(5) atoms. In the fourth Ni site, Ni(4) is bonded to one Se(2), one Se(3), and two equivalent Se(4) atoms to form a mixture of distorted corner and edge-sharing NiSe4 tetrahedra. In the fifth Ni site, Ni(5) is bonded to one Se(1), one Se(4), and two equivalent Se(3) atoms to form a mixture of distorted corner and edge-sharing NiSe4 tetrahedra. In the sixth Ni site, Ni(6) is bonded in a 5-coordinate geometry to one Se(1), two equivalent Se(3), and two equivalent Se(4) atoms. There are five inequivalent Se sites. In the first Se site, Se(5) is bonded in a 5-coordinate geometry to one Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the second Se site, Se(1) is bonded in a 6-coordinate geometry to one Ni(5), one Ni(6), two equivalent Ni(1), and two equivalent Ni(3) atoms. In the third Se site, Se(2) is bonded in a 5-coordinate geometry to one Ni(4), two equivalent Ni(1), and two equivalent Ni(2) atoms. In the fourth Se site, Se(3) is bonded in a 6-coordinate geometry to one Ni(2), one Ni(4), two equivalent Ni(5), and two equivalent Ni(6) atoms. In the fifth Se site, Se(4) is bonded in a 6-coordinate geometry to one Ni(3), one Ni(5), two equivalent Ni(4), and two equivalent Ni(6) atoms. is represented by the CIF card [CIF]
data_Ni6Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.491
_cell_length_b   6.252
_cell_length_c   16.998
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   73.788
_symmetry_Int_Tables_number   1
_cell_volume   356.227
_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  0.659  0.681  0.251  1.0
  Ni  Ni1  1  0.341  0.319  0.751  1.0
  Ni  Ni2  1  0.467  0.067  0.177  1.0
  Ni  Ni3  1  0.531  0.938  0.822  1.0
  Ni  Ni4  1  0.469  0.062  0.322  1.0
  Ni  Ni5  1  0.533  0.933  0.677  1.0
  Ni  Ni6  1  0.187  0.627  0.036  1.0
  Ni  Ni7  1  0.804  0.392  0.968  1.0
  Ni  Ni8  1  0.196  0.608  0.468  1.0
  Ni  Ni9  1  0.813  0.373  0.536  1.0
  Ni  Ni10  1  0.001  0.998  0.474  1.0
  Ni  Ni11  1  0.999  0.002  0.974  1.0
  Se  Se12  1  0.888  0.223  0.847  1.0
  Se  Se13  1  0.107  0.787  0.156  1.0
  Se  Se14  1  0.893  0.213  0.656  1.0
  Se  Se15  1  0.112  0.777  0.347  1.0
  Se  Se16  1  0.381  0.239  0.048  1.0
  Se  Se17  1  0.621  0.758  0.946  1.0
  Se  Se18  1  0.379  0.242  0.446  1.0
  Se  Se19  1  0.619  0.761  0.548  1.0
  Se  Se20  1  0.862  0.276  0.248  1.0
  Se  Se21  1  0.138  0.724  0.748  1.0
[/CIF]
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The compound described by Ni6Se5 crystallizes in the orthorhombic Cmc2_1 space group. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 5-coordinate geometry to one Se(5), two equivalent Se(1), and two equivalent Se(2) atoms. In the second Ni site, Ni(2) is bonded in a 5-coordinate geometry to one Se(3), two equivalent Se(2), and two equivalent Se(5) atoms. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one Se(4), two equivalent Se(1), and two equivalent Se(5) atoms. In the fourth Ni site, Ni(4) is bonded to one Se(2), one Se(3), and two equivalent Se(4) atoms to form a mixture of distorted corner and edge-sharing NiSe4 tetrahedra. In the fifth Ni site, Ni(5) is bonded to one Se(1), one Se(4), and two equivalent Se(3) atoms to form a mixture of distorted corner and edge-sharing NiSe4 tetrahedra. In the sixth Ni site, Ni(6) is bonded in a 5-coordinate geometry to one Se(1), two equivalent Se(3), and two equivalent Se(4) atoms. There are five inequivalent Se sites. In the first Se site, Se(5) is bonded in a 5-coordinate geometry to one Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the second Se site, Se(1) is bonded in a 6-coordinate geometry to one Ni(5), one Ni(6), two equivalent Ni(1), and two equivalent Ni(3) atoms. In the third Se site, Se(2) is bonded in a 5-coordinate geometry to one Ni(4), two equivalent Ni(1), and two equivalent Ni(2) atoms. In the fourth Se site, Se(3) is bonded in a 6-coordinate geometry to one Ni(2), one Ni(4), two equivalent Ni(5), and two equivalent Ni(6) atoms. In the fifth Se site, Se(4) is bonded in a 6-coordinate geometry to one Ni(3), one Ni(5), two equivalent Ni(4), and two equivalent Ni(6) atoms. is represented by the CIF card [CIF]
data_Ni6Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.491
_cell_length_b   6.252
_cell_length_c   16.998
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   73.788
_symmetry_Int_Tables_number   1
_cell_volume   356.227
_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  0.659  0.681  0.251  1.0
  Ni  Ni1  1  0.341  0.319  0.751  1.0
  Ni  Ni2  1  0.467  0.067  0.177  1.0
  Ni  Ni3  1  0.531  0.938  0.822  1.0
  Ni  Ni4  1  0.469  0.062  0.322  1.0
  Ni  Ni5  1  0.533  0.933  0.677  1.0
  Ni  Ni6  1  0.187  0.627  0.036  1.0
  Ni  Ni7  1  0.804  0.392  0.968  1.0
  Ni  Ni8  1  0.196  0.608  0.468  1.0
  Ni  Ni9  1  0.813  0.373  0.536  1.0
  Ni  Ni10  1  0.001  0.998  0.474  1.0
  Ni  Ni11  1  0.999  0.002  0.974  1.0
  Se  Se12  1  0.888  0.223  0.847  1.0
  Se  Se13  1  0.107  0.787  0.156  1.0
  Se  Se14  1  0.893  0.213  0.656  1.0
  Se  Se15  1  0.112  0.777  0.347  1.0
  Se  Se16  1  0.381  0.239  0.048  1.0
  Se  Se17  1  0.621  0.758  0.946  1.0
  Se  Se18  1  0.379  0.242  0.446  1.0
  Se  Se19  1  0.619  0.761  0.548  1.0
  Se  Se20  1  0.862  0.276  0.248  1.0
  Se  Se21  1  0.138  0.724  0.748  1.0
[/CIF]
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