The crystal structure described by Cr(FeSe2)2 crystallizes in the monoclinic C2/m space group. Cr(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form CrSe6 octahedra that share corners with twelve equivalent Fe(1)Se6 octahedra, edges with two equivalent Cr(1)Se6 octahedra, and faces with two equivalent Fe(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 53-56°. 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 Cr(1)Se6 octahedra, edges with six equivalent Fe(1)Se6 octahedra, and  a faceface with one Cr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 53-56°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Cr(1) and three equivalent Fe(1) atoms. In the second Se site, Se(2) is bonded in a distorted rectangular see-saw-like geometry to one Cr(1) and three equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr(FeSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.527
_cell_length_b   6.194
_cell_length_c   6.643
_cell_angle_alpha   115.933
_cell_angle_beta   105.394
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   124.688
_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
  Cr  Cr0  1  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.744  0.693  0.488  1.0
  Fe  Fe2  1  0.256  0.307  0.512  1.0
  Se  Se3  1  0.360  0.019  0.720  1.0
  Se  Se4  1  0.113  0.457  0.225  1.0
  Se  Se5  1  0.887  0.543  0.775  1.0
  Se  Se6  1  0.640  0.981  0.280  1.0
[/CIF]
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The crystal structure described by Cr(FeSe2)2 crystallizes in the monoclinic C2/m space group. Cr(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form CrSe6 octahedra that share corners with twelve equivalent Fe(1)Se6 octahedra, edges with two equivalent Cr(1)Se6 octahedra, and faces with two equivalent Fe(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 53-56°. 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 Cr(1)Se6 octahedra, edges with six equivalent Fe(1)Se6 octahedra, and  a faceface with one Cr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 53-56°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Cr(1) and three equivalent Fe(1) atoms. In the second Se site, Se(2) is bonded in a distorted rectangular see-saw-like geometry to one Cr(1) and three equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr(FeSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.527
_cell_length_b   6.194
_cell_length_c   6.643
_cell_angle_alpha   115.933
_cell_angle_beta   105.394
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   124.688
_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
  Cr  Cr0  1  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.744  0.693  0.488  1.0
  Fe  Fe2  1  0.256  0.307  0.512  1.0
  Se  Se3  1  0.360  0.019  0.720  1.0
  Se  Se4  1  0.113  0.457  0.225  1.0
  Se  Se5  1  0.887  0.543  0.775  1.0
  Se  Se6  1  0.640  0.981  0.280  1.0
[/CIF]
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