The material structure described by U3Sn7 crystallizes in the orthorhombic Cmmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 10-coordinate geometry to two equivalent Sn(1), two equivalent Sn(3), and six equivalent Sn(2) atoms. In the second U site, U(2) is bonded to four equivalent Sn(1), four equivalent Sn(3), and four equivalent Sn(4) atoms to form a mixture of face and corner-sharing USn12 cuboctahedra. There are four inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 4-coordinate geometry to two equivalent U(1) and two equivalent U(2) atoms. In the second Sn site, Sn(2) is bonded in a 8-coordinate geometry to six equivalent U(1) and two equivalent Sn(2) atoms. In the third Sn site, Sn(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent U(1) and two equivalent U(2) atoms. In the fourth Sn site, Sn(4) is bonded in a distorted square co-planar geometry to four equivalent U(2) atoms. is represented by the CIF file [CIF]
data_U3Sn7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.272
_cell_length_b   12.272
_cell_length_c   4.658
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   158.900
_symmetry_Int_Tables_number   1
_cell_volume   252.552
_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  0.808  0.192  0.000  1.0
  U  U1  1  0.192  0.808  0.000  1.0
  U  U2  1  0.000  0.000  0.000  1.0
  Sn  Sn3  1  0.901  0.099  0.500  1.0
  Sn  Sn4  1  0.099  0.901  0.500  1.0
  Sn  Sn5  1  0.706  0.294  0.500  1.0
  Sn  Sn6  1  0.294  0.706  0.500  1.0
  Sn  Sn7  1  0.597  0.403  0.000  1.0
  Sn  Sn8  1  0.403  0.597  0.000  1.0
  Sn  Sn9  1  0.500  0.500  0.500  1.0
[/CIF]
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The material structure described by U3Sn7 crystallizes in the orthorhombic Cmmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 10-coordinate geometry to two equivalent Sn(1), two equivalent Sn(3), and six equivalent Sn(2) atoms. In the second U site, U(2) is bonded to four equivalent Sn(1), four equivalent Sn(3), and four equivalent Sn(4) atoms to form a mixture of face and corner-sharing USn12 cuboctahedra. There are four inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 4-coordinate geometry to two equivalent U(1) and two equivalent U(2) atoms. In the second Sn site, Sn(2) is bonded in a 8-coordinate geometry to six equivalent U(1) and two equivalent Sn(2) atoms. In the third Sn site, Sn(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent U(1) and two equivalent U(2) atoms. In the fourth Sn site, Sn(4) is bonded in a distorted square co-planar geometry to four equivalent U(2) atoms. is represented by the CIF file [CIF]
data_U3Sn7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.272
_cell_length_b   12.272
_cell_length_c   4.658
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   158.900
_symmetry_Int_Tables_number   1
_cell_volume   252.552
_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  0.808  0.192  0.000  1.0
  U  U1  1  0.192  0.808  0.000  1.0
  U  U2  1  0.000  0.000  0.000  1.0
  Sn  Sn3  1  0.901  0.099  0.500  1.0
  Sn  Sn4  1  0.099  0.901  0.500  1.0
  Sn  Sn5  1  0.706  0.294  0.500  1.0
  Sn  Sn6  1  0.294  0.706  0.500  1.0
  Sn  Sn7  1  0.597  0.403  0.000  1.0
  Sn  Sn8  1  0.403  0.597  0.000  1.0
  Sn  Sn9  1  0.500  0.500  0.500  1.0
[/CIF]
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