The structure described by BaU2Se5 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 9-coordinate geometry to two equivalent Se(2), two equivalent Se(3), two equivalent Se(4), and three equivalent Se(5) atoms. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. In the second U site, U(2) is bonded to one Se(2), one Se(3), one Se(4), two equivalent Se(1), and two equivalent Se(5) atoms to form distorted edge-sharing USe7 pentagonal bipyramids. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form distorted SeU4 trigonal pyramids that share corners with four equivalent Se(2)Ba2U3 square pyramids, corners with two equivalent Se(3)Ba2U3 trigonal bipyramids, corners with two equivalent Se(4)Ba2U3 trigonal bipyramids, corners with two equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(2)Ba2U3 square pyramid, edges with two equivalent Se(3)Ba2U3 trigonal bipyramids, edges with two equivalent Se(4)Ba2U3 trigonal bipyramids, and  an edgeedge with one Se(1)U4 trigonal pyramid. In the second Se site, Se(2) is bonded to two equivalent Ba(1), one U(2), and two equivalent U(1) atoms to form distorted SeBa2U3 square pyramids that share corners with four equivalent Se(4)Ba2U3 trigonal bipyramids, corners with five equivalent Se(3)Ba2U3 trigonal bipyramids, corners with four equivalent Se(1)U4 trigonal pyramids, edges with two equivalent Se(2)Ba2U3 square pyramids,  an edgeedge with one Se(4)Ba2U3 trigonal bipyramid, edges with two equivalent Se(3)Ba2U3 trigonal bipyramids,  an edgeedge with one Se(1)U4 trigonal pyramid, and  a faceface with one Se(4)Ba2U3 trigonal bipyramid. In the third Se site, Se(3) is bonded to two equivalent Ba(1), one U(2), and two equivalent U(1) atoms to form distorted SeBa2U3 trigonal bipyramids that share corners with five equivalent Se(2)Ba2U3 square pyramids,  a cornercorner with one Se(4)Ba2U3 trigonal bipyramid, corners with four equivalent Se(3)Ba2U3 trigonal bipyramids, corners with two equivalent Se(1)U4 trigonal pyramids, edges with two equivalent Se(2)Ba2U3 square pyramids, edges with four equivalent Se(4)Ba2U3 trigonal bipyramids, and edges with two equivalent Se(1)U4 trigonal pyramids. In the fourth Se site, Se(4) is bonded to two equivalent Ba(1), one U(2), and two equivalent U(1) atoms to form distorted SeBa2U3 trigonal bipyramids that share corners with four equivalent Se(2)Ba2U3 square pyramids,  a cornercorner with one Se(3)Ba2U3 trigonal bipyramid, corners with four equivalent Se(4)Ba2U3 trigonal bipyramids, corners with two equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(2)Ba2U3 square pyramid, edges with four equivalent Se(3)Ba2U3 trigonal bipyramids, edges with two equivalent Se(1)U4 trigonal pyramids, and  a faceface with one Se(2)Ba2U3 square pyramid. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to three equivalent Ba(1) and two equivalent U(2) atoms. is represented by the CIF file [CIF]
data_BaU2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.952
_cell_length_b   8.867
_cell_length_c   12.387
_cell_angle_alpha   89.566
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   873.419
_cell_formula_units_Z   4
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  0.055  0.492  0.331  1.0
  Ba  Ba1  1  0.555  0.508  0.169  1.0
  Ba  Ba2  1  0.945  0.508  0.669  1.0
  Ba  Ba3  1  0.445  0.492  0.831  1.0
  U  U4  1  0.020  0.997  0.320  1.0
  U  U5  1  0.520  0.003  0.180  1.0
  U  U6  1  0.980  0.003  0.680  1.0
  U  U7  1  0.480  0.997  0.820  1.0
  U  U8  1  0.069  0.755  0.008  1.0
  U  U9  1  0.569  0.245  0.492  1.0
  U  U10  1  0.931  0.245  0.992  1.0
  U  U11  1  0.431  0.755  0.508  1.0
  Se  Se12  1  0.660  0.957  0.401  1.0
  Se  Se13  1  0.160  0.043  0.099  1.0
  Se  Se14  1  0.340  0.043  0.599  1.0
  Se  Se15  1  0.840  0.957  0.901  1.0
  Se  Se16  1  0.454  0.793  0.002  1.0
  Se  Se17  1  0.954  0.207  0.498  1.0
  Se  Se18  1  0.546  0.207  0.998  1.0
  Se  Se19  1  0.046  0.793  0.502  1.0
  Se  Se20  1  0.841  0.781  0.188  1.0
  Se  Se21  1  0.341  0.219  0.312  1.0
  Se  Se22  1  0.159  0.219  0.812  1.0
  Se  Se23  1  0.659  0.781  0.688  1.0
  Se  Se24  1  0.311  0.775  0.285  1.0
  Se  Se25  1  0.811  0.225  0.215  1.0
  Se  Se26  1  0.689  0.225  0.715  1.0
  Se  Se27  1  0.189  0.775  0.785  1.0
  Se  Se28  1  0.178  0.463  0.071  1.0
  Se  Se29  1  0.678  0.537  0.429  1.0
  Se  Se30  1  0.822  0.537  0.929  1.0
  Se  Se31  1  0.322  0.463  0.571  1.0
[/CIF]
.
The structure described by BaU2Se5 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 9-coordinate geometry to two equivalent Se(2), two equivalent Se(3), two equivalent Se(4), and three equivalent Se(5) atoms. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. In the second U site, U(2) is bonded to one Se(2), one Se(3), one Se(4), two equivalent Se(1), and two equivalent Se(5) atoms to form distorted edge-sharing USe7 pentagonal bipyramids. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent U(1) and two equivalent U(2) atoms to form distorted SeU4 trigonal pyramids that share corners with four equivalent Se(2)Ba2U3 square pyramids, corners with two equivalent Se(3)Ba2U3 trigonal bipyramids, corners with two equivalent Se(4)Ba2U3 trigonal bipyramids, corners with two equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(2)Ba2U3 square pyramid, edges with two equivalent Se(3)Ba2U3 trigonal bipyramids, edges with two equivalent Se(4)Ba2U3 trigonal bipyramids, and  an edgeedge with one Se(1)U4 trigonal pyramid. In the second Se site, Se(2) is bonded to two equivalent Ba(1), one U(2), and two equivalent U(1) atoms to form distorted SeBa2U3 square pyramids that share corners with four equivalent Se(4)Ba2U3 trigonal bipyramids, corners with five equivalent Se(3)Ba2U3 trigonal bipyramids, corners with four equivalent Se(1)U4 trigonal pyramids, edges with two equivalent Se(2)Ba2U3 square pyramids,  an edgeedge with one Se(4)Ba2U3 trigonal bipyramid, edges with two equivalent Se(3)Ba2U3 trigonal bipyramids,  an edgeedge with one Se(1)U4 trigonal pyramid, and  a faceface with one Se(4)Ba2U3 trigonal bipyramid. In the third Se site, Se(3) is bonded to two equivalent Ba(1), one U(2), and two equivalent U(1) atoms to form distorted SeBa2U3 trigonal bipyramids that share corners with five equivalent Se(2)Ba2U3 square pyramids,  a cornercorner with one Se(4)Ba2U3 trigonal bipyramid, corners with four equivalent Se(3)Ba2U3 trigonal bipyramids, corners with two equivalent Se(1)U4 trigonal pyramids, edges with two equivalent Se(2)Ba2U3 square pyramids, edges with four equivalent Se(4)Ba2U3 trigonal bipyramids, and edges with two equivalent Se(1)U4 trigonal pyramids. In the fourth Se site, Se(4) is bonded to two equivalent Ba(1), one U(2), and two equivalent U(1) atoms to form distorted SeBa2U3 trigonal bipyramids that share corners with four equivalent Se(2)Ba2U3 square pyramids,  a cornercorner with one Se(3)Ba2U3 trigonal bipyramid, corners with four equivalent Se(4)Ba2U3 trigonal bipyramids, corners with two equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(2)Ba2U3 square pyramid, edges with four equivalent Se(3)Ba2U3 trigonal bipyramids, edges with two equivalent Se(1)U4 trigonal pyramids, and  a faceface with one Se(2)Ba2U3 square pyramid. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to three equivalent Ba(1) and two equivalent U(2) atoms. is represented by the CIF file [CIF]
data_BaU2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.952
_cell_length_b   8.867
_cell_length_c   12.387
_cell_angle_alpha   89.566
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   873.419
_cell_formula_units_Z   4
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  0.055  0.492  0.331  1.0
  Ba  Ba1  1  0.555  0.508  0.169  1.0
  Ba  Ba2  1  0.945  0.508  0.669  1.0
  Ba  Ba3  1  0.445  0.492  0.831  1.0
  U  U4  1  0.020  0.997  0.320  1.0
  U  U5  1  0.520  0.003  0.180  1.0
  U  U6  1  0.980  0.003  0.680  1.0
  U  U7  1  0.480  0.997  0.820  1.0
  U  U8  1  0.069  0.755  0.008  1.0
  U  U9  1  0.569  0.245  0.492  1.0
  U  U10  1  0.931  0.245  0.992  1.0
  U  U11  1  0.431  0.755  0.508  1.0
  Se  Se12  1  0.660  0.957  0.401  1.0
  Se  Se13  1  0.160  0.043  0.099  1.0
  Se  Se14  1  0.340  0.043  0.599  1.0
  Se  Se15  1  0.840  0.957  0.901  1.0
  Se  Se16  1  0.454  0.793  0.002  1.0
  Se  Se17  1  0.954  0.207  0.498  1.0
  Se  Se18  1  0.546  0.207  0.998  1.0
  Se  Se19  1  0.046  0.793  0.502  1.0
  Se  Se20  1  0.841  0.781  0.188  1.0
  Se  Se21  1  0.341  0.219  0.312  1.0
  Se  Se22  1  0.159  0.219  0.812  1.0
  Se  Se23  1  0.659  0.781  0.688  1.0
  Se  Se24  1  0.311  0.775  0.285  1.0
  Se  Se25  1  0.811  0.225  0.215  1.0
  Se  Se26  1  0.689  0.225  0.715  1.0
  Se  Se27  1  0.189  0.775  0.785  1.0
  Se  Se28  1  0.178  0.463  0.071  1.0
  Se  Se29  1  0.678  0.537  0.429  1.0
  Se  Se30  1  0.822  0.537  0.929  1.0
  Se  Se31  1  0.322  0.463  0.571  1.0
[/CIF]
.