The crystal structure described by Ba4USe6 crystallizes in the trigonal R-3c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to six equivalent Se(1) atoms. U(1) is bonded in an octahedral geometry to six equivalent Se(1) atoms. Se(1) is bonded to one Ba(2), four equivalent Ba(1), and one U(1) atom to form a mixture of distorted face, corner, and edge-sharing SeBa5U octahedra. The corner-sharing octahedral tilt angles range from 0-67°. is represented by the CIF file [CIF]
data_Ba4USe6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.073
_cell_length_b   9.073
_cell_length_c   9.073
_cell_angle_alpha   89.476
_cell_angle_beta   89.476
_cell_angle_gamma   89.476
_symmetry_Int_Tables_number   1
_cell_volume   746.678
_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
  Ba  Ba0  1  0.876  0.624  0.250  1.0
  Ba  Ba1  1  0.250  0.876  0.624  1.0
  Ba  Ba2  1  0.624  0.250  0.876  1.0
  Ba  Ba3  1  0.750  0.124  0.376  1.0
  Ba  Ba4  1  0.376  0.750  0.124  1.0
  Ba  Ba5  1  0.124  0.376  0.750  1.0
  Ba  Ba6  1  0.250  0.250  0.250  1.0
  Ba  Ba7  1  0.750  0.750  0.750  1.0
  U  U8  1  0.500  0.500  0.500  1.0
  U  U9  1  0.000  0.000  0.000  1.0
  Se  Se10  1  0.202  0.561  0.423  1.0
  Se  Se11  1  0.423  0.202  0.561  1.0
  Se  Se12  1  0.561  0.423  0.202  1.0
  Se  Se13  1  0.923  0.061  0.702  1.0
  Se  Se14  1  0.702  0.923  0.061  1.0
  Se  Se15  1  0.061  0.702  0.923  1.0
  Se  Se16  1  0.798  0.439  0.577  1.0
  Se  Se17  1  0.577  0.798  0.439  1.0
  Se  Se18  1  0.439  0.577  0.798  1.0
  Se  Se19  1  0.077  0.939  0.298  1.0
  Se  Se20  1  0.298  0.077  0.939  1.0
  Se  Se21  1  0.939  0.298  0.077  1.0
[/CIF]
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The crystal structure described by Ba4USe6 crystallizes in the trigonal R-3c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to six equivalent Se(1) atoms. U(1) is bonded in an octahedral geometry to six equivalent Se(1) atoms. Se(1) is bonded to one Ba(2), four equivalent Ba(1), and one U(1) atom to form a mixture of distorted face, corner, and edge-sharing SeBa5U octahedra. The corner-sharing octahedral tilt angles range from 0-67°. is represented by the CIF file [CIF]
data_Ba4USe6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.073
_cell_length_b   9.073
_cell_length_c   9.073
_cell_angle_alpha   89.476
_cell_angle_beta   89.476
_cell_angle_gamma   89.476
_symmetry_Int_Tables_number   1
_cell_volume   746.678
_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
  Ba  Ba0  1  0.876  0.624  0.250  1.0
  Ba  Ba1  1  0.250  0.876  0.624  1.0
  Ba  Ba2  1  0.624  0.250  0.876  1.0
  Ba  Ba3  1  0.750  0.124  0.376  1.0
  Ba  Ba4  1  0.376  0.750  0.124  1.0
  Ba  Ba5  1  0.124  0.376  0.750  1.0
  Ba  Ba6  1  0.250  0.250  0.250  1.0
  Ba  Ba7  1  0.750  0.750  0.750  1.0
  U  U8  1  0.500  0.500  0.500  1.0
  U  U9  1  0.000  0.000  0.000  1.0
  Se  Se10  1  0.202  0.561  0.423  1.0
  Se  Se11  1  0.423  0.202  0.561  1.0
  Se  Se12  1  0.561  0.423  0.202  1.0
  Se  Se13  1  0.923  0.061  0.702  1.0
  Se  Se14  1  0.702  0.923  0.061  1.0
  Se  Se15  1  0.061  0.702  0.923  1.0
  Se  Se16  1  0.798  0.439  0.577  1.0
  Se  Se17  1  0.577  0.798  0.439  1.0
  Se  Se18  1  0.439  0.577  0.798  1.0
  Se  Se19  1  0.077  0.939  0.298  1.0
  Se  Se20  1  0.298  0.077  0.939  1.0
  Se  Se21  1  0.939  0.298  0.077  1.0
[/CIF]
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