The structure described by U3Pd20Si6 crystallizes in the orthorhombic Immm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a distorted tetrahedral geometry to two equivalent Pd(2) and two equivalent Pd(4) atoms. In the second U site, U(2) is bonded in a cuboctahedral geometry to two equivalent Pd(3), two equivalent Pd(5), and eight equivalent Pd(1) atoms. There are five inequivalent Pd sites. In the first Pd site, Pd(1) is bonded in a 2-coordinate geometry to one U(2), one Si(1), and one Si(2) atom. In the second Pd site, Pd(2) is bonded to one U(1), one Si(2), and two equivalent Si(1) atoms to form a mixture of corner and edge-sharing PdUSi3 tetrahedra. In the third Pd site, Pd(3) is bonded in a 2-coordinate geometry to one U(2) and two equivalent Si(1) atoms. In the fourth Pd site, Pd(4) is bonded to one U(1), one Si(2), and two equivalent Si(1) atoms to form a mixture of corner and edge-sharing PdUSi3 tetrahedra. In the fifth Pd site, Pd(5) is bonded in a 2-coordinate geometry to one U(2) and two equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to one Pd(3), one Pd(5), two equivalent Pd(1), two equivalent Pd(2), and two equivalent Pd(4) atoms. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to two equivalent Pd(2), two equivalent Pd(4), and four equivalent Pd(1) atoms. is represented by the CIF file [CIF]
data_U3(Si3Pd10)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.695
_cell_length_b   8.691
_cell_length_c   8.687
_cell_angle_alpha   60.076
_cell_angle_beta   59.996
_cell_angle_gamma   59.863
_symmetry_Int_Tables_number   1
_cell_volume   463.951
_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  0.250  0.250  0.250  1.0
  U  U1  1  0.750  0.750  0.750  1.0
  U  U2  1  1.000  0.000  0.000  1.0
  Si  Si3  1  0.733  0.267  0.267  1.0
  Si  Si4  1  0.267  0.733  0.267  1.0
  Si  Si5  1  0.267  0.733  0.733  1.0
  Si  Si6  1  0.732  0.732  0.268  1.0
  Si  Si7  1  0.733  0.267  0.733  1.0
  Si  Si8  1  0.268  0.268  0.732  1.0
  Pd  Pd9  1  1.000  0.654  1.000  1.0
  Pd  Pd10  1  0.384  0.847  0.385  1.0
  Pd  Pd11  1  1.000  0.654  0.346  1.0
  Pd  Pd12  1  0.346  1.000  0.000  1.0
  Pd  Pd13  1  0.654  0.346  1.000  1.0
  Pd  Pd14  1  0.616  0.153  0.615  1.0
  Pd  Pd15  1  0.654  1.000  0.347  1.0
  Pd  Pd16  1  0.847  0.384  0.384  1.0
  Pd  Pd17  1  0.346  0.000  0.653  1.0
  Pd  Pd18  1  0.385  0.384  0.384  1.0
  Pd  Pd19  1  0.000  0.999  0.654  1.0
  Pd  Pd20  1  1.000  0.001  0.346  1.0
  Pd  Pd21  1  0.615  0.616  0.616  1.0
  Pd  Pd22  1  0.153  0.616  0.616  1.0
  Pd  Pd23  1  0.616  0.615  0.153  1.0
  Pd  Pd24  1  0.346  0.654  0.000  1.0
  Pd  Pd25  1  0.000  0.346  0.000  1.0
  Pd  Pd26  1  0.384  0.385  0.847  1.0
  Pd  Pd27  1  0.000  0.346  0.654  1.0
  Pd  Pd28  1  0.654  0.000  1.000  1.0
[/CIF]
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The structure described by U3Pd20Si6 crystallizes in the orthorhombic Immm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a distorted tetrahedral geometry to two equivalent Pd(2) and two equivalent Pd(4) atoms. In the second U site, U(2) is bonded in a cuboctahedral geometry to two equivalent Pd(3), two equivalent Pd(5), and eight equivalent Pd(1) atoms. There are five inequivalent Pd sites. In the first Pd site, Pd(1) is bonded in a 2-coordinate geometry to one U(2), one Si(1), and one Si(2) atom. In the second Pd site, Pd(2) is bonded to one U(1), one Si(2), and two equivalent Si(1) atoms to form a mixture of corner and edge-sharing PdUSi3 tetrahedra. In the third Pd site, Pd(3) is bonded in a 2-coordinate geometry to one U(2) and two equivalent Si(1) atoms. In the fourth Pd site, Pd(4) is bonded to one U(1), one Si(2), and two equivalent Si(1) atoms to form a mixture of corner and edge-sharing PdUSi3 tetrahedra. In the fifth Pd site, Pd(5) is bonded in a 2-coordinate geometry to one U(2) and two equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to one Pd(3), one Pd(5), two equivalent Pd(1), two equivalent Pd(2), and two equivalent Pd(4) atoms. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to two equivalent Pd(2), two equivalent Pd(4), and four equivalent Pd(1) atoms. is represented by the CIF file [CIF]
data_U3(Si3Pd10)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.695
_cell_length_b   8.691
_cell_length_c   8.687
_cell_angle_alpha   60.076
_cell_angle_beta   59.996
_cell_angle_gamma   59.863
_symmetry_Int_Tables_number   1
_cell_volume   463.951
_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  0.250  0.250  0.250  1.0
  U  U1  1  0.750  0.750  0.750  1.0
  U  U2  1  1.000  0.000  0.000  1.0
  Si  Si3  1  0.733  0.267  0.267  1.0
  Si  Si4  1  0.267  0.733  0.267  1.0
  Si  Si5  1  0.267  0.733  0.733  1.0
  Si  Si6  1  0.732  0.732  0.268  1.0
  Si  Si7  1  0.733  0.267  0.733  1.0
  Si  Si8  1  0.268  0.268  0.732  1.0
  Pd  Pd9  1  1.000  0.654  1.000  1.0
  Pd  Pd10  1  0.384  0.847  0.385  1.0
  Pd  Pd11  1  1.000  0.654  0.346  1.0
  Pd  Pd12  1  0.346  1.000  0.000  1.0
  Pd  Pd13  1  0.654  0.346  1.000  1.0
  Pd  Pd14  1  0.616  0.153  0.615  1.0
  Pd  Pd15  1  0.654  1.000  0.347  1.0
  Pd  Pd16  1  0.847  0.384  0.384  1.0
  Pd  Pd17  1  0.346  0.000  0.653  1.0
  Pd  Pd18  1  0.385  0.384  0.384  1.0
  Pd  Pd19  1  0.000  0.999  0.654  1.0
  Pd  Pd20  1  1.000  0.001  0.346  1.0
  Pd  Pd21  1  0.615  0.616  0.616  1.0
  Pd  Pd22  1  0.153  0.616  0.616  1.0
  Pd  Pd23  1  0.616  0.615  0.153  1.0
  Pd  Pd24  1  0.346  0.654  0.000  1.0
  Pd  Pd25  1  0.000  0.346  0.000  1.0
  Pd  Pd26  1  0.384  0.385  0.847  1.0
  Pd  Pd27  1  0.000  0.346  0.654  1.0
  Pd  Pd28  1  0.654  0.000  1.000  1.0
[/CIF]
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