The compound described by NiSe2 is Pyrite structured and crystallizes in the orthorhombic Pbca space group. Ni(1) is bonded to six equivalent Se(1) atoms to form NiSe6 octahedra that share corners with twelve equivalent Ni(1)Se6 octahedra and corners with six equivalent Se(1)Ni3Se tetrahedra. The corner-sharing octahedral tilt angles range from 64-65°. Se(1) is bonded to three equivalent Ni(1) and one Se(1) atom to form distorted SeNi3Se tetrahedra that share corners with three equivalent Ni(1)Se6 octahedra and corners with fifteen equivalent Se(1)Ni3Se tetrahedra. The corner-sharing octahedral tilt angles range from 77-78°. is represented by the CIF card [CIF]
data_NiSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.026
_cell_length_b   6.048
_cell_length_c   6.005
_cell_angle_alpha   90.002
_cell_angle_beta   89.999
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   218.835
_cell_formula_units_Z   4
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  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.500  0.000  0.500  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.000  0.500  0.500  1.0
  Se  Se4  1  0.385  0.385  0.387  1.0
  Se  Se5  1  0.115  0.615  0.887  1.0
  Se  Se6  1  0.885  0.115  0.613  1.0
  Se  Se7  1  0.615  0.885  0.113  1.0
  Se  Se8  1  0.615  0.615  0.613  1.0
  Se  Se9  1  0.885  0.385  0.113  1.0
  Se  Se10  1  0.115  0.885  0.387  1.0
  Se  Se11  1  0.385  0.115  0.887  1.0
[/CIF]
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The compound described by NiSe2 is Pyrite structured and crystallizes in the orthorhombic Pbca space group. Ni(1) is bonded to six equivalent Se(1) atoms to form NiSe6 octahedra that share corners with twelve equivalent Ni(1)Se6 octahedra and corners with six equivalent Se(1)Ni3Se tetrahedra. The corner-sharing octahedral tilt angles range from 64-65°. Se(1) is bonded to three equivalent Ni(1) and one Se(1) atom to form distorted SeNi3Se tetrahedra that share corners with three equivalent Ni(1)Se6 octahedra and corners with fifteen equivalent Se(1)Ni3Se tetrahedra. The corner-sharing octahedral tilt angles range from 77-78°. is represented by the CIF card [CIF]
data_NiSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.026
_cell_length_b   6.048
_cell_length_c   6.005
_cell_angle_alpha   90.002
_cell_angle_beta   89.999
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   218.835
_cell_formula_units_Z   4
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  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.500  0.000  0.500  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.000  0.500  0.500  1.0
  Se  Se4  1  0.385  0.385  0.387  1.0
  Se  Se5  1  0.115  0.615  0.887  1.0
  Se  Se6  1  0.885  0.115  0.613  1.0
  Se  Se7  1  0.615  0.885  0.113  1.0
  Se  Se8  1  0.615  0.615  0.613  1.0
  Se  Se9  1  0.885  0.385  0.113  1.0
  Se  Se10  1  0.115  0.885  0.387  1.0
  Se  Se11  1  0.385  0.115  0.887  1.0
[/CIF]
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