The structure described by U2Se3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to two equivalent Se(2), two equivalent Se(3), and three equivalent Se(1) atoms to form a mixture of distorted corner and edge-sharing USe7 pentagonal bipyramids. In the second U site, U(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and three equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent U(2) and three equivalent U(1) atoms to form a mixture of corner and edge-sharing SeU5 square pyramids. In the second Se site, Se(2) is bonded to two equivalent U(1) and three equivalent U(2) atoms to form a mixture of distorted corner and edge-sharing SeU5 trigonal bipyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent U(1) and three equivalent U(2) atoms. is represented by the CIF card [CIF]
data_U2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.067
_cell_length_b   11.136
_cell_length_c   11.358
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   514.405
_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
  U  U0  1  0.750  0.815  0.487  1.0
  U  U1  1  0.750  0.495  0.308  1.0
  U  U2  1  0.250  0.995  0.192  1.0
  U  U3  1  0.750  0.005  0.808  1.0
  U  U4  1  0.250  0.315  0.013  1.0
  U  U5  1  0.750  0.685  0.987  1.0
  U  U6  1  0.250  0.505  0.692  1.0
  U  U7  1  0.250  0.185  0.513  1.0
  Se  Se8  1  0.250  0.555  0.120  1.0
  Se  Se9  1  0.750  0.371  0.547  1.0
  Se  Se10  1  0.250  0.629  0.453  1.0
  Se  Se11  1  0.250  0.298  0.272  1.0
  Se  Se12  1  0.250  0.202  0.772  1.0
  Se  Se13  1  0.750  0.129  0.047  1.0
  Se  Se14  1  0.750  0.702  0.728  1.0
  Se  Se15  1  0.250  0.871  0.953  1.0
  Se  Se16  1  0.750  0.798  0.228  1.0
  Se  Se17  1  0.750  0.055  0.380  1.0
  Se  Se18  1  0.750  0.445  0.880  1.0
  Se  Se19  1  0.250  0.945  0.620  1.0
[/CIF]
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The structure described by U2Se3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to two equivalent Se(2), two equivalent Se(3), and three equivalent Se(1) atoms to form a mixture of distorted corner and edge-sharing USe7 pentagonal bipyramids. In the second U site, U(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and three equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent U(2) and three equivalent U(1) atoms to form a mixture of corner and edge-sharing SeU5 square pyramids. In the second Se site, Se(2) is bonded to two equivalent U(1) and three equivalent U(2) atoms to form a mixture of distorted corner and edge-sharing SeU5 trigonal bipyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent U(1) and three equivalent U(2) atoms. is represented by the CIF card [CIF]
data_U2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.067
_cell_length_b   11.136
_cell_length_c   11.358
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   514.405
_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
  U  U0  1  0.750  0.815  0.487  1.0
  U  U1  1  0.750  0.495  0.308  1.0
  U  U2  1  0.250  0.995  0.192  1.0
  U  U3  1  0.750  0.005  0.808  1.0
  U  U4  1  0.250  0.315  0.013  1.0
  U  U5  1  0.750  0.685  0.987  1.0
  U  U6  1  0.250  0.505  0.692  1.0
  U  U7  1  0.250  0.185  0.513  1.0
  Se  Se8  1  0.250  0.555  0.120  1.0
  Se  Se9  1  0.750  0.371  0.547  1.0
  Se  Se10  1  0.250  0.629  0.453  1.0
  Se  Se11  1  0.250  0.298  0.272  1.0
  Se  Se12  1  0.250  0.202  0.772  1.0
  Se  Se13  1  0.750  0.129  0.047  1.0
  Se  Se14  1  0.750  0.702  0.728  1.0
  Se  Se15  1  0.250  0.871  0.953  1.0
  Se  Se16  1  0.750  0.798  0.228  1.0
  Se  Se17  1  0.750  0.055  0.380  1.0
  Se  Se18  1  0.750  0.445  0.880  1.0
  Se  Se19  1  0.250  0.945  0.620  1.0
[/CIF]
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