The material described by U3Se5 crystallizes in the orthorhombic Pnma space group. 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), and four equivalent Se(1) atoms to form distorted edge-sharing USe7 pentagonal bipyramids. There are four 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 two equivalent Se(4)U5 square pyramids, corners with four equivalent Se(3)U5 square pyramids, corners with two equivalent Se(2)U5 trigonal bipyramids, corners with six equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(3)U5 square pyramid, edges with two equivalent Se(4)U5 square pyramids, edges with two equivalent Se(2)U5 trigonal bipyramids, and  an edgeedge with one Se(1)U4 trigonal pyramid. In the second Se site, Se(2) is bonded to one U(2) and four equivalent U(1) atoms to form distorted SeU5 trigonal bipyramids that share  a cornercorner with one Se(4)U5 square pyramid, corners with five equivalent Se(3)U5 square pyramids, corners with four equivalent Se(2)U5 trigonal bipyramids, corners with four equivalent Se(1)U4 trigonal pyramids, edges with two equivalent Se(3)U5 square pyramids, edges with four equivalent Se(4)U5 square pyramids, and edges with four equivalent Se(1)U4 trigonal pyramids. In the third Se site, Se(3) is bonded to one U(2) and four equivalent U(1) atoms to form SeU5 square pyramids that share corners with four equivalent Se(4)U5 square pyramids, corners with five equivalent Se(2)U5 trigonal bipyramids, corners with eight equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(4)U5 square pyramid, edges with two equivalent Se(3)U5 square pyramids, edges with two equivalent Se(2)U5 trigonal bipyramids, edges with two equivalent Se(1)U4 trigonal pyramids, and  a faceface with one Se(4)U5 square pyramid. In the fourth Se site, Se(4) is bonded to one U(2) and four equivalent U(1) atoms to form distorted SeU5 square pyramids that share corners with four equivalent Se(3)U5 square pyramids, corners with four equivalent Se(4)U5 square pyramids,  a cornercorner with one Se(2)U5 trigonal bipyramid, corners with four equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(3)U5 square pyramid, edges with four equivalent Se(2)U5 trigonal bipyramids, edges with four equivalent Se(1)U4 trigonal pyramids, and  a faceface with one Se(3)U5 square pyramid. is represented by the CIF card [CIF]
data_U3Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.841
_cell_length_b   8.380
_cell_length_c   12.474
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   819.729
_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  0.521  0.499  0.321  1.0
  U  U1  1  0.979  0.001  0.821  1.0
  U  U2  1  0.479  0.999  0.679  1.0
  U  U3  1  0.021  0.501  0.179  1.0
  U  U4  1  0.479  0.501  0.679  1.0
  U  U5  1  0.021  0.999  0.179  1.0
  U  U6  1  0.521  0.001  0.321  1.0
  U  U7  1  0.979  0.499  0.821  1.0
  U  U8  1  0.074  0.750  0.492  1.0
  U  U9  1  0.426  0.750  0.992  1.0
  U  U10  1  0.926  0.250  0.508  1.0
  U  U11  1  0.574  0.250  0.008  1.0
  Se  Se12  1  0.836  0.956  0.599  1.0
  Se  Se13  1  0.664  0.544  0.099  1.0
  Se  Se14  1  0.164  0.456  0.401  1.0
  Se  Se15  1  0.336  0.044  0.901  1.0
  Se  Se16  1  0.164  0.044  0.401  1.0
  Se  Se17  1  0.336  0.456  0.901  1.0
  Se  Se18  1  0.836  0.544  0.599  1.0
  Se  Se19  1  0.664  0.956  0.099  1.0
  Se  Se20  1  0.828  0.750  0.315  1.0
  Se  Se21  1  0.672  0.750  0.815  1.0
  Se  Se22  1  0.172  0.250  0.685  1.0
  Se  Se23  1  0.328  0.250  0.185  1.0
  Se  Se24  1  0.459  0.750  0.501  1.0
  Se  Se25  1  0.041  0.750  0.001  1.0
  Se  Se26  1  0.541  0.250  0.499  1.0
  Se  Se27  1  0.959  0.250  0.999  1.0
  Se  Se28  1  0.198  0.750  0.716  1.0
  Se  Se29  1  0.302  0.750  0.216  1.0
  Se  Se30  1  0.802  0.250  0.284  1.0
  Se  Se31  1  0.698  0.250  0.784  1.0
[/CIF]
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The material described by U3Se5 crystallizes in the orthorhombic Pnma space group. 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), and four equivalent Se(1) atoms to form distorted edge-sharing USe7 pentagonal bipyramids. There are four 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 two equivalent Se(4)U5 square pyramids, corners with four equivalent Se(3)U5 square pyramids, corners with two equivalent Se(2)U5 trigonal bipyramids, corners with six equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(3)U5 square pyramid, edges with two equivalent Se(4)U5 square pyramids, edges with two equivalent Se(2)U5 trigonal bipyramids, and  an edgeedge with one Se(1)U4 trigonal pyramid. In the second Se site, Se(2) is bonded to one U(2) and four equivalent U(1) atoms to form distorted SeU5 trigonal bipyramids that share  a cornercorner with one Se(4)U5 square pyramid, corners with five equivalent Se(3)U5 square pyramids, corners with four equivalent Se(2)U5 trigonal bipyramids, corners with four equivalent Se(1)U4 trigonal pyramids, edges with two equivalent Se(3)U5 square pyramids, edges with four equivalent Se(4)U5 square pyramids, and edges with four equivalent Se(1)U4 trigonal pyramids. In the third Se site, Se(3) is bonded to one U(2) and four equivalent U(1) atoms to form SeU5 square pyramids that share corners with four equivalent Se(4)U5 square pyramids, corners with five equivalent Se(2)U5 trigonal bipyramids, corners with eight equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(4)U5 square pyramid, edges with two equivalent Se(3)U5 square pyramids, edges with two equivalent Se(2)U5 trigonal bipyramids, edges with two equivalent Se(1)U4 trigonal pyramids, and  a faceface with one Se(4)U5 square pyramid. In the fourth Se site, Se(4) is bonded to one U(2) and four equivalent U(1) atoms to form distorted SeU5 square pyramids that share corners with four equivalent Se(3)U5 square pyramids, corners with four equivalent Se(4)U5 square pyramids,  a cornercorner with one Se(2)U5 trigonal bipyramid, corners with four equivalent Se(1)U4 trigonal pyramids,  an edgeedge with one Se(3)U5 square pyramid, edges with four equivalent Se(2)U5 trigonal bipyramids, edges with four equivalent Se(1)U4 trigonal pyramids, and  a faceface with one Se(3)U5 square pyramid. is represented by the CIF card [CIF]
data_U3Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.841
_cell_length_b   8.380
_cell_length_c   12.474
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   819.729
_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  0.521  0.499  0.321  1.0
  U  U1  1  0.979  0.001  0.821  1.0
  U  U2  1  0.479  0.999  0.679  1.0
  U  U3  1  0.021  0.501  0.179  1.0
  U  U4  1  0.479  0.501  0.679  1.0
  U  U5  1  0.021  0.999  0.179  1.0
  U  U6  1  0.521  0.001  0.321  1.0
  U  U7  1  0.979  0.499  0.821  1.0
  U  U8  1  0.074  0.750  0.492  1.0
  U  U9  1  0.426  0.750  0.992  1.0
  U  U10  1  0.926  0.250  0.508  1.0
  U  U11  1  0.574  0.250  0.008  1.0
  Se  Se12  1  0.836  0.956  0.599  1.0
  Se  Se13  1  0.664  0.544  0.099  1.0
  Se  Se14  1  0.164  0.456  0.401  1.0
  Se  Se15  1  0.336  0.044  0.901  1.0
  Se  Se16  1  0.164  0.044  0.401  1.0
  Se  Se17  1  0.336  0.456  0.901  1.0
  Se  Se18  1  0.836  0.544  0.599  1.0
  Se  Se19  1  0.664  0.956  0.099  1.0
  Se  Se20  1  0.828  0.750  0.315  1.0
  Se  Se21  1  0.672  0.750  0.815  1.0
  Se  Se22  1  0.172  0.250  0.685  1.0
  Se  Se23  1  0.328  0.250  0.185  1.0
  Se  Se24  1  0.459  0.750  0.501  1.0
  Se  Se25  1  0.041  0.750  0.001  1.0
  Se  Se26  1  0.541  0.250  0.499  1.0
  Se  Se27  1  0.959  0.250  0.999  1.0
  Se  Se28  1  0.198  0.750  0.716  1.0
  Se  Se29  1  0.302  0.750  0.216  1.0
  Se  Se30  1  0.802  0.250  0.284  1.0
  Se  Se31  1  0.698  0.250  0.784  1.0
[/CIF]
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