The material structure described by UFeSe3 crystallizes in the orthorhombic Cmcm space group. U(1) is bonded in a 8-coordinate geometry to two equivalent Se(2) and six equivalent Se(1) atoms. Fe(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of corner and edge-sharing FeSe6 octahedra. The corner-sharing octahedral tilt angles are 46°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent U(1) and two equivalent Fe(1) atoms to form distorted SeU3Fe2 trigonal bipyramids that share corners with four equivalent Se(2)U2Fe2 tetrahedra, corners with nine equivalent Se(1)U3Fe2 trigonal bipyramids, edges with three equivalent Se(2)U2Fe2 tetrahedra, and edges with six equivalent Se(1)U3Fe2 trigonal bipyramids. In the second Se site, Se(2) is bonded to two equivalent U(1) and two equivalent Fe(1) atoms to form distorted SeU2Fe2 tetrahedra that share corners with four equivalent Se(2)U2Fe2 tetrahedra, corners with eight equivalent Se(1)U3Fe2 trigonal bipyramids, and edges with six equivalent Se(1)U3Fe2 trigonal bipyramids. is represented by the CIF file [CIF]
data_UFeSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.304
_cell_length_b   6.304
_cell_length_c   9.187
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   144.196
_symmetry_Int_Tables_number   1
_cell_volume   213.558
_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
  U  U0  1  0.244  0.756  0.250  1.0
  U  U1  1  0.756  0.244  0.750  1.0
  Fe  Fe2  1  0.000  0.000  0.500  1.0
  Fe  Fe3  1  0.000  0.000  0.000  1.0
  Se  Se4  1  0.641  0.359  0.443  1.0
  Se  Se5  1  0.359  0.641  0.557  1.0
  Se  Se6  1  0.641  0.359  0.057  1.0
  Se  Se7  1  0.359  0.641  0.943  1.0
  Se  Se8  1  0.919  0.081  0.250  1.0
  Se  Se9  1  0.081  0.919  0.750  1.0
[/CIF]
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The material structure described by UFeSe3 crystallizes in the orthorhombic Cmcm space group. U(1) is bonded in a 8-coordinate geometry to two equivalent Se(2) and six equivalent Se(1) atoms. Fe(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form a mixture of corner and edge-sharing FeSe6 octahedra. The corner-sharing octahedral tilt angles are 46°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent U(1) and two equivalent Fe(1) atoms to form distorted SeU3Fe2 trigonal bipyramids that share corners with four equivalent Se(2)U2Fe2 tetrahedra, corners with nine equivalent Se(1)U3Fe2 trigonal bipyramids, edges with three equivalent Se(2)U2Fe2 tetrahedra, and edges with six equivalent Se(1)U3Fe2 trigonal bipyramids. In the second Se site, Se(2) is bonded to two equivalent U(1) and two equivalent Fe(1) atoms to form distorted SeU2Fe2 tetrahedra that share corners with four equivalent Se(2)U2Fe2 tetrahedra, corners with eight equivalent Se(1)U3Fe2 trigonal bipyramids, and edges with six equivalent Se(1)U3Fe2 trigonal bipyramids. is represented by the CIF file [CIF]
data_UFeSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.304
_cell_length_b   6.304
_cell_length_c   9.187
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   144.196
_symmetry_Int_Tables_number   1
_cell_volume   213.558
_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
  U  U0  1  0.244  0.756  0.250  1.0
  U  U1  1  0.756  0.244  0.750  1.0
  Fe  Fe2  1  0.000  0.000  0.500  1.0
  Fe  Fe3  1  0.000  0.000  0.000  1.0
  Se  Se4  1  0.641  0.359  0.443  1.0
  Se  Se5  1  0.359  0.641  0.557  1.0
  Se  Se6  1  0.641  0.359  0.057  1.0
  Se  Se7  1  0.359  0.641  0.943  1.0
  Se  Se8  1  0.919  0.081  0.250  1.0
  Se  Se9  1  0.081  0.919  0.750  1.0
[/CIF]
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