The material described by CoNi2Se4 crystallizes in the monoclinic C2/m space group. Co(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CoSe6 octahedra that share corners with twelve equivalent Ni(1)Se6 octahedra, edges with two equivalent Co(1)Se6 octahedra, and faces with two equivalent Ni(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 48-55°. Ni(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form distorted NiSe6 octahedra that share corners with six equivalent Co(1)Se6 octahedra, edges with six equivalent Ni(1)Se6 octahedra, and  a faceface with one Co(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 48-55°. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Co(1) and three equivalent Ni(1) atoms. In the second Se site, Se(1) is bonded to one Co(1) and three equivalent Ni(1) atoms to form a mixture of distorted edge and corner-sharing SeCoNi3 trigonal pyramids. is represented by the CIF file [CIF]
data_Co(NiSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.189
_cell_length_b   6.189
_cell_length_c   6.165
_cell_angle_alpha   62.286
_cell_angle_beta   62.286
_cell_angle_gamma   34.153
_symmetry_Int_Tables_number   1
_cell_volume   115.823
_cell_formula_units_Z   1
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
  Co  Co0  1  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.736  0.736  0.290  1.0
  Ni  Ni2  1  0.264  0.264  0.710  1.0
  Se  Se3  1  0.886  0.886  0.451  1.0
  Se  Se4  1  0.114  0.114  0.549  1.0
  Se  Se5  1  0.633  0.633  0.021  1.0
  Se  Se6  1  0.367  0.367  0.979  1.0
[/CIF]
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The material described by CoNi2Se4 crystallizes in the monoclinic C2/m space group. Co(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CoSe6 octahedra that share corners with twelve equivalent Ni(1)Se6 octahedra, edges with two equivalent Co(1)Se6 octahedra, and faces with two equivalent Ni(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 48-55°. Ni(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form distorted NiSe6 octahedra that share corners with six equivalent Co(1)Se6 octahedra, edges with six equivalent Ni(1)Se6 octahedra, and  a faceface with one Co(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 48-55°. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Co(1) and three equivalent Ni(1) atoms. In the second Se site, Se(1) is bonded to one Co(1) and three equivalent Ni(1) atoms to form a mixture of distorted edge and corner-sharing SeCoNi3 trigonal pyramids. is represented by the CIF file [CIF]
data_Co(NiSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.189
_cell_length_b   6.189
_cell_length_c   6.165
_cell_angle_alpha   62.286
_cell_angle_beta   62.286
_cell_angle_gamma   34.153
_symmetry_Int_Tables_number   1
_cell_volume   115.823
_cell_formula_units_Z   1
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
  Co  Co0  1  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.736  0.736  0.290  1.0
  Ni  Ni2  1  0.264  0.264  0.710  1.0
  Se  Se3  1  0.886  0.886  0.451  1.0
  Se  Se4  1  0.114  0.114  0.549  1.0
  Se  Se5  1  0.633  0.633  0.021  1.0
  Se  Se6  1  0.367  0.367  0.979  1.0
[/CIF]
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