The material structure described by USe2 crystallizes in the triclinic P1 space group. There are ten inequivalent U sites. In the first U site, U(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(10), one Se(13), one Se(16), one Se(18), one Se(20), one Se(5), and one Se(6) atom. In the second U site, U(2) is bonded in a 8-coordinate geometry to one Se(14), one Se(15), one Se(19), one Se(2), one Se(20), one Se(5), one Se(7), and one Se(9) atom. In the third U site, U(3) is bonded in a 8-coordinate geometry to one Se(11), one Se(15), one Se(17), one Se(18), one Se(3), one Se(6), one Se(8), and one Se(9) atom. In the fourth U site, U(4) is bonded in a 8-coordinate geometry to one Se(10), one Se(12), one Se(16), one Se(17), one Se(19), one Se(4), one Se(7), and one Se(8) atom. In the fifth U site, U(5) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), one Se(3), one Se(4), one Se(5), one Se(6), one Se(7), and one Se(8) atom. In the sixth U site, U(6) is bonded in a 8-coordinate geometry to one Se(11), one Se(12), one Se(15), one Se(17), one Se(2), one Se(4), one Se(7), and one Se(9) atom. In the seventh U site, U(7) is bonded in a 8-coordinate geometry to one Se(10), one Se(11), one Se(13), one Se(16), one Se(18), one Se(3), one Se(4), and one Se(8) atom. In the eighth U site, U(8) is bonded in a 8-coordinate geometry to one Se(1), one Se(10), one Se(12), one Se(14), one Se(16), one Se(19), one Se(2), and one Se(5) atom. In the ninth U site, U(9) is bonded in a 8-coordinate geometry to one Se(1), one Se(13), one Se(14), one Se(15), one Se(20), one Se(3), one Se(6), and one Se(9) atom. In the tenth U site, U(10) is bonded in a 8-coordinate geometry to one Se(11), one Se(12), one Se(13), one Se(14), one Se(17), one Se(18), one Se(19), and one Se(20) atom. There are twenty inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted rectangular see-saw-like geometry to one U(1), one U(5), one U(8), and one U(9) atom. In the second Se site, Se(2) is bonded in a distorted rectangular see-saw-like geometry to one U(2), one U(5), one U(6), and one U(8) atom. In the third Se site, Se(3) is bonded in a distorted rectangular see-saw-like geometry to one U(3), one U(5), one U(7), and one U(9) atom. In the fourth Se site, Se(4) is bonded in a distorted rectangular see-saw-like geometry to one U(4), one U(5), one U(6), and one U(7) atom. In the fifth Se site, Se(5) is bonded to one U(1), one U(2), one U(5), and one U(8) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the sixth Se site, Se(6) is bonded to one U(1), one U(3), one U(5), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the seventh Se site, Se(7) is bonded to one U(2), one U(4), one U(5), and one U(6) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the eighth Se site, Se(8) is bonded to one U(3), one U(4), one U(5), and one U(7) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the ninth Se site, Se(9) is bonded to one U(2), one U(3), one U(6), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 tetrahedra. In the tenth Se site, Se(10) is bonded to one U(1), one U(4), one U(7), and one U(8) atom to form a mixture of edge and corner-sharing SeU4 tetrahedra. In the eleventh Se site, Se(11) is bonded to one U(10), one U(3), one U(6), and one U(7) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the twelfth Se site, Se(12) is bonded to one U(10), one U(4), one U(6), and one U(8) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the thirteenth Se site, Se(13) is bonded to one U(1), one U(10), one U(7), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the fourteenth Se site, Se(14) is bonded to one U(10), one U(2), one U(8), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the fifteenth Se site, Se(15) is bonded to one U(2), one U(3), one U(6), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 tetrahedra. In the sixteenth Se site, Se(16) is bonded to one U(1), one U(4), one U(7), and one U(8) atom to form a mixture of edge and corner-sharing SeU4 tetrahedra. In the seventeenth Se site, Se(17) is bonded in a distorted rectangular see-saw-like geometry to one U(10), one U(3), one U(4), and one U(6) atom. In the eighteenth Se site, Se(18) is bonded in a distorted rectangular see-saw-like geometry to one U(1), one U(10), one U(3), and one U(7) atom. In the nineteenth Se site, Se(19) is bonded in a distorted rectangular see-saw-like geometry to one U(10), one U(2), one U(4), and one U(8) atom. In the twentieth Se site, Se(20) is bonded in a distorted rectangular see-saw-like geometry to one U(1), one U(10), one U(2), and one U(9) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_USe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.775
_cell_length_b   10.776
_cell_length_c   6.636
_cell_angle_alpha   89.992
_cell_angle_beta   89.993
_cell_angle_gamma   90.006
_symmetry_Int_Tables_number   1
_cell_volume   770.545
_cell_formula_units_Z   10
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  0.841  0.153  0.248  1.0
  U  U1  1  0.651  0.661  0.247  1.0
  U  U2  1  0.349  0.339  0.246  1.0
  U  U3  1  0.159  0.847  0.251  1.0
  U  U4  1  0.500  0.000  0.851  1.0
  U  U5  1  0.339  0.651  0.755  1.0
  U  U6  1  0.153  0.159  0.750  1.0
  U  U7  1  0.846  0.841  0.751  1.0
  U  U8  1  0.661  0.349  0.752  1.0
  U  U9  1  0.000  0.500  0.150  1.0
  Se  Se10  1  0.711  0.093  0.620  1.0
  Se  Se11  1  0.591  0.790  0.621  1.0
  Se  Se12  1  0.409  0.209  0.620  1.0
  Se  Se13  1  0.289  0.908  0.621  1.0
  Se  Se14  1  0.707  0.913  0.107  1.0
  Se  Se15  1  0.590  0.209  0.106  1.0
  Se  Se16  1  0.410  0.792  0.107  1.0
  Se  Se17  1  0.293  0.087  0.107  1.0
  Se  Se18  1  0.500  0.500  1.000  1.0
  Se  Se19  1  0.000  1.000  1.000  1.0
  Se  Se20  1  0.208  0.410  0.893  1.0
  Se  Se21  1  0.087  0.707  0.894  1.0
  Se  Se22  1  0.913  0.294  0.893  1.0
  Se  Se23  1  0.792  0.589  0.894  1.0
  Se  Se24  1  0.500  0.500  0.500  1.0
  Se  Se25  1  1.000  0.000  0.500  1.0
  Se  Se26  1  0.209  0.591  0.380  1.0
  Se  Se27  1  0.093  0.289  0.379  1.0
  Se  Se28  1  0.907  0.711  0.380  1.0
  Se  Se29  1  0.791  0.409  0.380  1.0
[/CIF]
.
The material structure described by USe2 crystallizes in the triclinic P1 space group. There are ten inequivalent U sites. In the first U site, U(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(10), one Se(13), one Se(16), one Se(18), one Se(20), one Se(5), and one Se(6) atom. In the second U site, U(2) is bonded in a 8-coordinate geometry to one Se(14), one Se(15), one Se(19), one Se(2), one Se(20), one Se(5), one Se(7), and one Se(9) atom. In the third U site, U(3) is bonded in a 8-coordinate geometry to one Se(11), one Se(15), one Se(17), one Se(18), one Se(3), one Se(6), one Se(8), and one Se(9) atom. In the fourth U site, U(4) is bonded in a 8-coordinate geometry to one Se(10), one Se(12), one Se(16), one Se(17), one Se(19), one Se(4), one Se(7), and one Se(8) atom. In the fifth U site, U(5) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), one Se(3), one Se(4), one Se(5), one Se(6), one Se(7), and one Se(8) atom. In the sixth U site, U(6) is bonded in a 8-coordinate geometry to one Se(11), one Se(12), one Se(15), one Se(17), one Se(2), one Se(4), one Se(7), and one Se(9) atom. In the seventh U site, U(7) is bonded in a 8-coordinate geometry to one Se(10), one Se(11), one Se(13), one Se(16), one Se(18), one Se(3), one Se(4), and one Se(8) atom. In the eighth U site, U(8) is bonded in a 8-coordinate geometry to one Se(1), one Se(10), one Se(12), one Se(14), one Se(16), one Se(19), one Se(2), and one Se(5) atom. In the ninth U site, U(9) is bonded in a 8-coordinate geometry to one Se(1), one Se(13), one Se(14), one Se(15), one Se(20), one Se(3), one Se(6), and one Se(9) atom. In the tenth U site, U(10) is bonded in a 8-coordinate geometry to one Se(11), one Se(12), one Se(13), one Se(14), one Se(17), one Se(18), one Se(19), and one Se(20) atom. There are twenty inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted rectangular see-saw-like geometry to one U(1), one U(5), one U(8), and one U(9) atom. In the second Se site, Se(2) is bonded in a distorted rectangular see-saw-like geometry to one U(2), one U(5), one U(6), and one U(8) atom. In the third Se site, Se(3) is bonded in a distorted rectangular see-saw-like geometry to one U(3), one U(5), one U(7), and one U(9) atom. In the fourth Se site, Se(4) is bonded in a distorted rectangular see-saw-like geometry to one U(4), one U(5), one U(6), and one U(7) atom. In the fifth Se site, Se(5) is bonded to one U(1), one U(2), one U(5), and one U(8) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the sixth Se site, Se(6) is bonded to one U(1), one U(3), one U(5), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the seventh Se site, Se(7) is bonded to one U(2), one U(4), one U(5), and one U(6) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the eighth Se site, Se(8) is bonded to one U(3), one U(4), one U(5), and one U(7) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the ninth Se site, Se(9) is bonded to one U(2), one U(3), one U(6), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 tetrahedra. In the tenth Se site, Se(10) is bonded to one U(1), one U(4), one U(7), and one U(8) atom to form a mixture of edge and corner-sharing SeU4 tetrahedra. In the eleventh Se site, Se(11) is bonded to one U(10), one U(3), one U(6), and one U(7) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the twelfth Se site, Se(12) is bonded to one U(10), one U(4), one U(6), and one U(8) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the thirteenth Se site, Se(13) is bonded to one U(1), one U(10), one U(7), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the fourteenth Se site, Se(14) is bonded to one U(10), one U(2), one U(8), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 trigonal pyramids. In the fifteenth Se site, Se(15) is bonded to one U(2), one U(3), one U(6), and one U(9) atom to form a mixture of edge and corner-sharing SeU4 tetrahedra. In the sixteenth Se site, Se(16) is bonded to one U(1), one U(4), one U(7), and one U(8) atom to form a mixture of edge and corner-sharing SeU4 tetrahedra. In the seventeenth Se site, Se(17) is bonded in a distorted rectangular see-saw-like geometry to one U(10), one U(3), one U(4), and one U(6) atom. In the eighteenth Se site, Se(18) is bonded in a distorted rectangular see-saw-like geometry to one U(1), one U(10), one U(3), and one U(7) atom. In the nineteenth Se site, Se(19) is bonded in a distorted rectangular see-saw-like geometry to one U(10), one U(2), one U(4), and one U(8) atom. In the twentieth Se site, Se(20) is bonded in a distorted rectangular see-saw-like geometry to one U(1), one U(10), one U(2), and one U(9) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_USe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.775
_cell_length_b   10.776
_cell_length_c   6.636
_cell_angle_alpha   89.992
_cell_angle_beta   89.993
_cell_angle_gamma   90.006
_symmetry_Int_Tables_number   1
_cell_volume   770.545
_cell_formula_units_Z   10
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  0.841  0.153  0.248  1.0
  U  U1  1  0.651  0.661  0.247  1.0
  U  U2  1  0.349  0.339  0.246  1.0
  U  U3  1  0.159  0.847  0.251  1.0
  U  U4  1  0.500  0.000  0.851  1.0
  U  U5  1  0.339  0.651  0.755  1.0
  U  U6  1  0.153  0.159  0.750  1.0
  U  U7  1  0.846  0.841  0.751  1.0
  U  U8  1  0.661  0.349  0.752  1.0
  U  U9  1  0.000  0.500  0.150  1.0
  Se  Se10  1  0.711  0.093  0.620  1.0
  Se  Se11  1  0.591  0.790  0.621  1.0
  Se  Se12  1  0.409  0.209  0.620  1.0
  Se  Se13  1  0.289  0.908  0.621  1.0
  Se  Se14  1  0.707  0.913  0.107  1.0
  Se  Se15  1  0.590  0.209  0.106  1.0
  Se  Se16  1  0.410  0.792  0.107  1.0
  Se  Se17  1  0.293  0.087  0.107  1.0
  Se  Se18  1  0.500  0.500  1.000  1.0
  Se  Se19  1  0.000  1.000  1.000  1.0
  Se  Se20  1  0.208  0.410  0.893  1.0
  Se  Se21  1  0.087  0.707  0.894  1.0
  Se  Se22  1  0.913  0.294  0.893  1.0
  Se  Se23  1  0.792  0.589  0.894  1.0
  Se  Se24  1  0.500  0.500  0.500  1.0
  Se  Se25  1  1.000  0.000  0.500  1.0
  Se  Se26  1  0.209  0.591  0.380  1.0
  Se  Se27  1  0.093  0.289  0.379  1.0
  Se  Se28  1  0.907  0.711  0.380  1.0
  Se  Se29  1  0.791  0.409  0.380  1.0
[/CIF]
.