The material described by Ba2U(Cu2Se3)2 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and three equivalent Se(3) atoms. U(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form USe6 octahedra that share edges with four equivalent Cu(2)Se4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. In the second Cu site, Cu(2) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with two equivalent Cu(2)Se4 tetrahedra and edges with two equivalent U(1)Se6 octahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to two equivalent Ba(1), one U(1), two equivalent Cu(1), and two equivalent Cu(2) atoms. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to three equivalent Ba(1), one U(1), one Cu(1), and one Cu(2) atom. In the third Se site, Se(3) is bonded to three equivalent Ba(1), one U(1), one Cu(1), and one Cu(2) atom to form a mixture of distorted corner and edge-sharing SeBa3UCu2 pentagonal pyramids. is represented by the CIF file [CIF]
data_Ba2U(Cu2Se3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.830
_cell_length_b   7.338
_cell_length_c   8.959
_cell_angle_alpha   72.312
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   615.636
_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  0.268  0.485  0.124  1.0
  Ba  Ba1  1  0.768  0.515  0.376  1.0
  Ba  Ba2  1  0.732  0.515  0.876  1.0
  Ba  Ba3  1  0.232  0.485  0.624  1.0
  U  U4  1  0.000  0.000  0.000  1.0
  U  U5  1  0.500  0.000  0.500  1.0
  Cu  Cu6  1  0.001  0.995  0.360  1.0
  Cu  Cu7  1  0.501  0.005  0.140  1.0
  Cu  Cu8  1  0.999  0.005  0.640  1.0
  Cu  Cu9  1  0.499  0.995  0.860  1.0
  Cu  Cu10  1  0.253  0.935  0.265  1.0
  Cu  Cu11  1  0.753  0.065  0.235  1.0
  Cu  Cu12  1  0.747  0.065  0.735  1.0
  Cu  Cu13  1  0.247  0.935  0.765  1.0
  Se  Se14  1  0.718  0.888  0.030  1.0
  Se  Se15  1  0.218  0.112  0.470  1.0
  Se  Se16  1  0.282  0.112  0.970  1.0
  Se  Se17  1  0.782  0.888  0.530  1.0
  Se  Se18  1  0.449  0.717  0.352  1.0
  Se  Se19  1  0.949  0.283  0.148  1.0
  Se  Se20  1  0.551  0.283  0.648  1.0
  Se  Se21  1  0.051  0.717  0.852  1.0
  Se  Se22  1  0.062  0.712  0.289  1.0
  Se  Se23  1  0.562  0.288  0.211  1.0
  Se  Se24  1  0.938  0.288  0.711  1.0
  Se  Se25  1  0.438  0.712  0.789  1.0
[/CIF]
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The material described by Ba2U(Cu2Se3)2 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and three equivalent Se(3) atoms. U(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form USe6 octahedra that share edges with four equivalent Cu(2)Se4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. In the second Cu site, Cu(2) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with two equivalent Cu(2)Se4 tetrahedra and edges with two equivalent U(1)Se6 octahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to two equivalent Ba(1), one U(1), two equivalent Cu(1), and two equivalent Cu(2) atoms. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to three equivalent Ba(1), one U(1), one Cu(1), and one Cu(2) atom. In the third Se site, Se(3) is bonded to three equivalent Ba(1), one U(1), one Cu(1), and one Cu(2) atom to form a mixture of distorted corner and edge-sharing SeBa3UCu2 pentagonal pyramids. is represented by the CIF file [CIF]
data_Ba2U(Cu2Se3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.830
_cell_length_b   7.338
_cell_length_c   8.959
_cell_angle_alpha   72.312
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   615.636
_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  0.268  0.485  0.124  1.0
  Ba  Ba1  1  0.768  0.515  0.376  1.0
  Ba  Ba2  1  0.732  0.515  0.876  1.0
  Ba  Ba3  1  0.232  0.485  0.624  1.0
  U  U4  1  0.000  0.000  0.000  1.0
  U  U5  1  0.500  0.000  0.500  1.0
  Cu  Cu6  1  0.001  0.995  0.360  1.0
  Cu  Cu7  1  0.501  0.005  0.140  1.0
  Cu  Cu8  1  0.999  0.005  0.640  1.0
  Cu  Cu9  1  0.499  0.995  0.860  1.0
  Cu  Cu10  1  0.253  0.935  0.265  1.0
  Cu  Cu11  1  0.753  0.065  0.235  1.0
  Cu  Cu12  1  0.747  0.065  0.735  1.0
  Cu  Cu13  1  0.247  0.935  0.765  1.0
  Se  Se14  1  0.718  0.888  0.030  1.0
  Se  Se15  1  0.218  0.112  0.470  1.0
  Se  Se16  1  0.282  0.112  0.970  1.0
  Se  Se17  1  0.782  0.888  0.530  1.0
  Se  Se18  1  0.449  0.717  0.352  1.0
  Se  Se19  1  0.949  0.283  0.148  1.0
  Se  Se20  1  0.551  0.283  0.648  1.0
  Se  Se21  1  0.051  0.717  0.852  1.0
  Se  Se22  1  0.062  0.712  0.289  1.0
  Se  Se23  1  0.562  0.288  0.211  1.0
  Se  Se24  1  0.938  0.288  0.711  1.0
  Se  Se25  1  0.438  0.712  0.789  1.0
[/CIF]
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