The material structure described by BaFe2Se4 crystallizes in the tetragonal I4/m space group. Ba(1) is bonded to twelve equivalent Se(1) atoms to form BaSe12 cuboctahedra that share corners with eight equivalent Fe(1)Se4 tetrahedra, edges with eight equivalent Ba(1)Se12 cuboctahedra, edges with eight equivalent Fe(1)Se4 tetrahedra, and faces with two equivalent Ba(1)Se12 cuboctahedra. Fe(1) is bonded to four equivalent Se(1) atoms to form FeSe4 tetrahedra that share corners with four equivalent Ba(1)Se12 cuboctahedra, edges with four equivalent Ba(1)Se12 cuboctahedra, and edges with two equivalent Fe(1)Se4 tetrahedra. Se(1) is bonded in a 5-coordinate geometry to three equivalent Ba(1) and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_Ba(FeSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.213
_cell_length_b   6.213
_cell_length_c   6.213
_cell_angle_alpha   100.412
_cell_angle_beta   100.412
_cell_angle_gamma   129.684
_symmetry_Int_Tables_number   1
_cell_volume   167.067
_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
  Ba  Ba0  1  0.500  0.500  0.000  1.0
  Fe  Fe1  1  0.750  0.250  0.500  1.0
  Fe  Fe2  1  0.250  0.750  0.500  1.0
  Se  Se3  1  0.300  0.120  0.420  1.0
  Se  Se4  1  0.700  0.880  0.580  1.0
  Se  Se5  1  0.880  0.300  0.180  1.0
  Se  Se6  1  0.120  0.700  0.820  1.0
[/CIF]
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The material structure described by BaFe2Se4 crystallizes in the tetragonal I4/m space group. Ba(1) is bonded to twelve equivalent Se(1) atoms to form BaSe12 cuboctahedra that share corners with eight equivalent Fe(1)Se4 tetrahedra, edges with eight equivalent Ba(1)Se12 cuboctahedra, edges with eight equivalent Fe(1)Se4 tetrahedra, and faces with two equivalent Ba(1)Se12 cuboctahedra. Fe(1) is bonded to four equivalent Se(1) atoms to form FeSe4 tetrahedra that share corners with four equivalent Ba(1)Se12 cuboctahedra, edges with four equivalent Ba(1)Se12 cuboctahedra, and edges with two equivalent Fe(1)Se4 tetrahedra. Se(1) is bonded in a 5-coordinate geometry to three equivalent Ba(1) and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_Ba(FeSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.213
_cell_length_b   6.213
_cell_length_c   6.213
_cell_angle_alpha   100.412
_cell_angle_beta   100.412
_cell_angle_gamma   129.684
_symmetry_Int_Tables_number   1
_cell_volume   167.067
_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
  Ba  Ba0  1  0.500  0.500  0.000  1.0
  Fe  Fe1  1  0.750  0.250  0.500  1.0
  Fe  Fe2  1  0.250  0.750  0.500  1.0
  Se  Se3  1  0.300  0.120  0.420  1.0
  Se  Se4  1  0.700  0.880  0.580  1.0
  Se  Se5  1  0.880  0.300  0.180  1.0
  Se  Se6  1  0.120  0.700  0.820  1.0
[/CIF]
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