The crystal structure described by Co3Se4 is Hausmannite structured and crystallizes in the tetragonal I4_1/amd space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to four equivalent Se(1) atoms to form corner-sharing CoSe4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. In the second Co site, Co(2) is bonded to six equivalent Se(1) atoms to form CoSe6 octahedra that share corners with six equivalent Co(1)Se4 tetrahedra and edges with six equivalent Co(2)Se6 octahedra. Se(1) is bonded to one Co(1) and three equivalent Co(2) atoms to form a mixture of distorted edge and corner-sharing SeCo4 trigonal pyramids. is represented by the CIF file [CIF]
data_Co3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.047
_cell_length_b   7.048
_cell_length_c   7.059
_cell_angle_alpha   59.942
_cell_angle_beta   59.945
_cell_angle_gamma   60.131
_symmetry_Int_Tables_number   1
_cell_volume   247.933
_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
  Co  Co0  1  0.125  0.125  0.125  1.0
  Co  Co1  1  0.875  0.875  0.875  1.0
  Co  Co2  1  0.500  0.500  0.500  1.0
  Co  Co3  1  0.500  0.500  1.000  1.0
  Co  Co4  1  1.000  0.500  0.500  1.0
  Co  Co5  1  0.500  1.000  0.500  1.0
  Se  Se6  1  0.261  0.261  0.263  1.0
  Se  Se7  1  0.739  0.739  0.285  1.0
  Se  Se8  1  0.285  0.737  0.739  1.0
  Se  Se9  1  0.737  0.285  0.739  1.0
  Se  Se10  1  0.715  0.263  0.261  1.0
  Se  Se11  1  0.263  0.715  0.261  1.0
  Se  Se12  1  0.261  0.261  0.715  1.0
  Se  Se13  1  0.739  0.739  0.737  1.0
[/CIF]
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The crystal structure described by Co3Se4 is Hausmannite structured and crystallizes in the tetragonal I4_1/amd space group. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to four equivalent Se(1) atoms to form corner-sharing CoSe4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. In the second Co site, Co(2) is bonded to six equivalent Se(1) atoms to form CoSe6 octahedra that share corners with six equivalent Co(1)Se4 tetrahedra and edges with six equivalent Co(2)Se6 octahedra. Se(1) is bonded to one Co(1) and three equivalent Co(2) atoms to form a mixture of distorted edge and corner-sharing SeCo4 trigonal pyramids. is represented by the CIF file [CIF]
data_Co3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.047
_cell_length_b   7.048
_cell_length_c   7.059
_cell_angle_alpha   59.942
_cell_angle_beta   59.945
_cell_angle_gamma   60.131
_symmetry_Int_Tables_number   1
_cell_volume   247.933
_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
  Co  Co0  1  0.125  0.125  0.125  1.0
  Co  Co1  1  0.875  0.875  0.875  1.0
  Co  Co2  1  0.500  0.500  0.500  1.0
  Co  Co3  1  0.500  0.500  1.000  1.0
  Co  Co4  1  1.000  0.500  0.500  1.0
  Co  Co5  1  0.500  1.000  0.500  1.0
  Se  Se6  1  0.261  0.261  0.263  1.0
  Se  Se7  1  0.739  0.739  0.285  1.0
  Se  Se8  1  0.285  0.737  0.739  1.0
  Se  Se9  1  0.737  0.285  0.739  1.0
  Se  Se10  1  0.715  0.263  0.261  1.0
  Se  Se11  1  0.263  0.715  0.261  1.0
  Se  Se12  1  0.261  0.261  0.715  1.0
  Se  Se13  1  0.739  0.739  0.737  1.0
[/CIF]
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