The structure described by Fe2CoSe4 crystallizes in the monoclinic C2/m space group. Fe(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form distorted FeSe6 octahedra that share corners with six equivalent Co(1)Se6 octahedra, edges with six equivalent Fe(1)Se6 octahedra, and  a faceface with one Co(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. Co(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form CoSe6 octahedra that share corners with twelve equivalent Fe(1)Se6 octahedra, edges with two equivalent Co(1)Se6 octahedra, and faces with two equivalent Fe(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a 4-coordinate geometry to three equivalent Fe(1) and one Co(1) atom. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to three equivalent Fe(1) and two equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_Fe2CoSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.340
_cell_length_b   6.340
_cell_length_c   6.088
_cell_angle_alpha   64.035
_cell_angle_beta   64.035
_cell_angle_gamma   31.801
_symmetry_Int_Tables_number   1
_cell_volume   114.813
_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
  Fe  Fe0  1  0.259  0.259  0.694  1.0
  Fe  Fe1  1  0.741  0.741  0.306  1.0
  Co  Co2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.364  0.364  0.979  1.0
  Se  Se4  1  0.636  0.636  0.021  1.0
  Se  Se5  1  0.107  0.107  0.555  1.0
  Se  Se6  1  0.893  0.893  0.445  1.0
[/CIF]
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The structure described by Fe2CoSe4 crystallizes in the monoclinic C2/m space group. Fe(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form distorted FeSe6 octahedra that share corners with six equivalent Co(1)Se6 octahedra, edges with six equivalent Fe(1)Se6 octahedra, and  a faceface with one Co(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. Co(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form CoSe6 octahedra that share corners with twelve equivalent Fe(1)Se6 octahedra, edges with two equivalent Co(1)Se6 octahedra, and faces with two equivalent Fe(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 52-55°. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded in a 4-coordinate geometry to three equivalent Fe(1) and one Co(1) atom. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to three equivalent Fe(1) and two equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_Fe2CoSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.340
_cell_length_b   6.340
_cell_length_c   6.088
_cell_angle_alpha   64.035
_cell_angle_beta   64.035
_cell_angle_gamma   31.801
_symmetry_Int_Tables_number   1
_cell_volume   114.813
_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
  Fe  Fe0  1  0.259  0.259  0.694  1.0
  Fe  Fe1  1  0.741  0.741  0.306  1.0
  Co  Co2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.364  0.364  0.979  1.0
  Se  Se4  1  0.636  0.636  0.021  1.0
  Se  Se5  1  0.107  0.107  0.555  1.0
  Se  Se6  1  0.893  0.893  0.445  1.0
[/CIF]
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