The crystal structure described by Cr3Se is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to four equivalent Cr(1), four equivalent Cr(2), and four equivalent Se(1) atoms to form distorted CrCr8Se4 cuboctahedra that share corners with twelve equivalent Cr(1)Cr8Se4 cuboctahedra, edges with eight equivalent Cr(1)Cr8Se4 cuboctahedra, edges with eight equivalent Se(1)Cr12 cuboctahedra, faces with four equivalent Se(1)Cr12 cuboctahedra, and faces with ten equivalent Cr(1)Cr8Se4 cuboctahedra. In the second Cr site, Cr(2) is bonded in a square co-planar geometry to eight equivalent Cr(1) and four equivalent Se(1) atoms. Se(1) is bonded to four equivalent Cr(2) and eight equivalent Cr(1) atoms to form SeCr12 cuboctahedra that share corners with four equivalent Se(1)Cr12 cuboctahedra, edges with eight equivalent Se(1)Cr12 cuboctahedra, edges with sixteen equivalent Cr(1)Cr8Se4 cuboctahedra, faces with four equivalent Se(1)Cr12 cuboctahedra, and faces with eight equivalent Cr(1)Cr8Se4 cuboctahedra. is represented by the CIF file [CIF]
data_Cr3Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.797
_cell_length_b   4.797
_cell_length_c   4.797
_cell_angle_alpha   137.556
_cell_angle_beta   137.556
_cell_angle_gamma   61.583
_symmetry_Int_Tables_number   1
_cell_volume   49.706
_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  0.750  0.250  0.500  1.0
  Cr  Cr1  1  0.250  0.750  0.500  1.0
  Cr  Cr2  1  0.500  0.500  0.000  1.0
  Se  Se3  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Cr3Se is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to four equivalent Cr(1), four equivalent Cr(2), and four equivalent Se(1) atoms to form distorted CrCr8Se4 cuboctahedra that share corners with twelve equivalent Cr(1)Cr8Se4 cuboctahedra, edges with eight equivalent Cr(1)Cr8Se4 cuboctahedra, edges with eight equivalent Se(1)Cr12 cuboctahedra, faces with four equivalent Se(1)Cr12 cuboctahedra, and faces with ten equivalent Cr(1)Cr8Se4 cuboctahedra. In the second Cr site, Cr(2) is bonded in a square co-planar geometry to eight equivalent Cr(1) and four equivalent Se(1) atoms. Se(1) is bonded to four equivalent Cr(2) and eight equivalent Cr(1) atoms to form SeCr12 cuboctahedra that share corners with four equivalent Se(1)Cr12 cuboctahedra, edges with eight equivalent Se(1)Cr12 cuboctahedra, edges with sixteen equivalent Cr(1)Cr8Se4 cuboctahedra, faces with four equivalent Se(1)Cr12 cuboctahedra, and faces with eight equivalent Cr(1)Cr8Se4 cuboctahedra. is represented by the CIF file [CIF]
data_Cr3Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.797
_cell_length_b   4.797
_cell_length_c   4.797
_cell_angle_alpha   137.556
_cell_angle_beta   137.556
_cell_angle_gamma   61.583
_symmetry_Int_Tables_number   1
_cell_volume   49.706
_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  0.750  0.250  0.500  1.0
  Cr  Cr1  1  0.250  0.750  0.500  1.0
  Cr  Cr2  1  0.500  0.500  0.000  1.0
  Se  Se3  1  0.000  0.000  0.000  1.0
[/CIF]
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