The structure described by U7Se12 crystallizes in the hexagonal P-6 space group. There are three inequivalent U sites. In the first U site, U(1) is bonded in a 9-coordinate geometry to three equivalent Se(1) and six equivalent Se(2) atoms. In the second U site, U(2) is bonded in a 8-coordinate geometry to one Se(1), one Se(3), two equivalent Se(2), and four equivalent Se(4) atoms. In the third U site, U(3) is bonded in a 8-coordinate geometry to one Se(2), one Se(4), two equivalent Se(1), and four equivalent Se(3) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one U(1), one U(2), and two equivalent U(3) atoms to form SeU4 tetrahedra that share corners with four equivalent Se(1)U4 tetrahedra, corners with two equivalent Se(2)U5 trigonal bipyramids, corners with two equivalent Se(4)U5 trigonal bipyramids, corners with five equivalent Se(3)U5 trigonal bipyramids, edges with two equivalent Se(3)U5 trigonal bipyramids, edges with two equivalent Se(4)U5 trigonal bipyramids, and edges with four equivalent Se(2)U5 trigonal bipyramids. In the second Se site, Se(2) is bonded to one U(3), two equivalent U(1), and two equivalent U(2) atoms to form distorted SeU5 trigonal bipyramids that share corners with two equivalent Se(1)U4 tetrahedra, corners with two equivalent Se(3)U5 trigonal bipyramids, corners with four equivalent Se(2)U5 trigonal bipyramids, corners with five equivalent Se(4)U5 trigonal bipyramids, edges with four equivalent Se(1)U4 tetrahedra, edges with two equivalent Se(3)U5 trigonal bipyramids, edges with two equivalent Se(4)U5 trigonal bipyramids, and edges with four equivalent Se(2)U5 trigonal bipyramids. In the third Se site, Se(3) is bonded to one U(2) and four equivalent U(3) atoms to form distorted SeU5 trigonal bipyramids that share corners with five equivalent Se(1)U4 tetrahedra, corners with two equivalent Se(2)U5 trigonal bipyramids, corners with four equivalent Se(3)U5 trigonal bipyramids, corners with four equivalent Se(4)U5 trigonal bipyramids, edges with two equivalent Se(1)U4 tetrahedra, edges with two equivalent Se(2)U5 trigonal bipyramids, edges with two equivalent Se(4)U5 trigonal bipyramids, and edges with four equivalent Se(3)U5 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to one U(3) and four equivalent U(2) atoms to form distorted SeU5 trigonal bipyramids that share corners with two equivalent Se(1)U4 tetrahedra, corners with four equivalent Se(3)U5 trigonal bipyramids, corners with four equivalent Se(4)U5 trigonal bipyramids, corners with five equivalent Se(2)U5 trigonal bipyramids, edges with two equivalent Se(1)U4 tetrahedra, edges with two equivalent Se(2)U5 trigonal bipyramids, edges with two equivalent Se(3)U5 trigonal bipyramids, and edges with four equivalent Se(4)U5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_U7Se12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.027
_cell_length_b   11.626
_cell_length_c   11.626
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   471.342
_cell_formula_units_Z   1
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  0.000  0.000  1.0
  U  U1  1  0.750  0.428  0.279  1.0
  U  U2  1  0.750  0.721  0.149  1.0
  U  U3  1  0.750  0.851  0.572  1.0
  U  U4  1  0.250  0.559  0.709  1.0
  U  U5  1  0.250  0.291  0.850  1.0
  U  U6  1  0.250  0.150  0.441  1.0
  Se  Se7  1  0.750  0.249  0.995  1.0
  Se  Se8  1  0.750  0.005  0.253  1.0
  Se  Se9  1  0.750  0.747  0.751  1.0
  Se  Se10  1  0.250  0.792  0.002  1.0
  Se  Se11  1  0.250  0.998  0.790  1.0
  Se  Se12  1  0.250  0.210  0.208  1.0
  Se  Se13  1  0.750  0.141  0.629  1.0
  Se  Se14  1  0.750  0.371  0.511  1.0
  Se  Se15  1  0.750  0.489  0.859  1.0
  Se  Se16  1  0.250  0.860  0.386  1.0
  Se  Se17  1  0.250  0.614  0.474  1.0
  Se  Se18  1  0.250  0.526  0.140  1.0
[/CIF]
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The structure described by U7Se12 crystallizes in the hexagonal P-6 space group. There are three inequivalent U sites. In the first U site, U(1) is bonded in a 9-coordinate geometry to three equivalent Se(1) and six equivalent Se(2) atoms. In the second U site, U(2) is bonded in a 8-coordinate geometry to one Se(1), one Se(3), two equivalent Se(2), and four equivalent Se(4) atoms. In the third U site, U(3) is bonded in a 8-coordinate geometry to one Se(2), one Se(4), two equivalent Se(1), and four equivalent Se(3) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one U(1), one U(2), and two equivalent U(3) atoms to form SeU4 tetrahedra that share corners with four equivalent Se(1)U4 tetrahedra, corners with two equivalent Se(2)U5 trigonal bipyramids, corners with two equivalent Se(4)U5 trigonal bipyramids, corners with five equivalent Se(3)U5 trigonal bipyramids, edges with two equivalent Se(3)U5 trigonal bipyramids, edges with two equivalent Se(4)U5 trigonal bipyramids, and edges with four equivalent Se(2)U5 trigonal bipyramids. In the second Se site, Se(2) is bonded to one U(3), two equivalent U(1), and two equivalent U(2) atoms to form distorted SeU5 trigonal bipyramids that share corners with two equivalent Se(1)U4 tetrahedra, corners with two equivalent Se(3)U5 trigonal bipyramids, corners with four equivalent Se(2)U5 trigonal bipyramids, corners with five equivalent Se(4)U5 trigonal bipyramids, edges with four equivalent Se(1)U4 tetrahedra, edges with two equivalent Se(3)U5 trigonal bipyramids, edges with two equivalent Se(4)U5 trigonal bipyramids, and edges with four equivalent Se(2)U5 trigonal bipyramids. In the third Se site, Se(3) is bonded to one U(2) and four equivalent U(3) atoms to form distorted SeU5 trigonal bipyramids that share corners with five equivalent Se(1)U4 tetrahedra, corners with two equivalent Se(2)U5 trigonal bipyramids, corners with four equivalent Se(3)U5 trigonal bipyramids, corners with four equivalent Se(4)U5 trigonal bipyramids, edges with two equivalent Se(1)U4 tetrahedra, edges with two equivalent Se(2)U5 trigonal bipyramids, edges with two equivalent Se(4)U5 trigonal bipyramids, and edges with four equivalent Se(3)U5 trigonal bipyramids. In the fourth Se site, Se(4) is bonded to one U(3) and four equivalent U(2) atoms to form distorted SeU5 trigonal bipyramids that share corners with two equivalent Se(1)U4 tetrahedra, corners with four equivalent Se(3)U5 trigonal bipyramids, corners with four equivalent Se(4)U5 trigonal bipyramids, corners with five equivalent Se(2)U5 trigonal bipyramids, edges with two equivalent Se(1)U4 tetrahedra, edges with two equivalent Se(2)U5 trigonal bipyramids, edges with two equivalent Se(3)U5 trigonal bipyramids, and edges with four equivalent Se(4)U5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_U7Se12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.027
_cell_length_b   11.626
_cell_length_c   11.626
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   471.342
_cell_formula_units_Z   1
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  0.000  0.000  1.0
  U  U1  1  0.750  0.428  0.279  1.0
  U  U2  1  0.750  0.721  0.149  1.0
  U  U3  1  0.750  0.851  0.572  1.0
  U  U4  1  0.250  0.559  0.709  1.0
  U  U5  1  0.250  0.291  0.850  1.0
  U  U6  1  0.250  0.150  0.441  1.0
  Se  Se7  1  0.750  0.249  0.995  1.0
  Se  Se8  1  0.750  0.005  0.253  1.0
  Se  Se9  1  0.750  0.747  0.751  1.0
  Se  Se10  1  0.250  0.792  0.002  1.0
  Se  Se11  1  0.250  0.998  0.790  1.0
  Se  Se12  1  0.250  0.210  0.208  1.0
  Se  Se13  1  0.750  0.141  0.629  1.0
  Se  Se14  1  0.750  0.371  0.511  1.0
  Se  Se15  1  0.750  0.489  0.859  1.0
  Se  Se16  1  0.250  0.860  0.386  1.0
  Se  Se17  1  0.250  0.614  0.474  1.0
  Se  Se18  1  0.250  0.526  0.140  1.0
[/CIF]
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