The compound described by U6Fe5Al8Si9 crystallizes in the orthorhombic Immm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 12-coordinate geometry to two equivalent Fe(2), two equivalent Al(3), two equivalent Al(4), two equivalent Si(1), and four equivalent Si(2) atoms. In the second U site, U(2) is bonded in a 14-coordinate geometry to three equivalent Fe(1), one Al(3), one Al(4), two equivalent Al(1), two equivalent Al(2), one Si(3), two equivalent Si(1), and two equivalent Si(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(2) is bonded to four equivalent U(1), four equivalent Al(4), and four equivalent Si(2) atoms to form distorted face-sharing FeU4Al4Si4 cuboctahedra. In the second Fe site, Fe(1) is bonded in a 8-coordinate geometry to three equivalent U(2), one Al(3), one Si(2), and three equivalent Si(1) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to four equivalent U(2), two equivalent Al(2), two equivalent Al(3), two equivalent Si(1), and two equivalent Si(3) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to four equivalent U(2), two equivalent Al(1), two equivalent Al(4), two equivalent Si(2), and two equivalent Si(3) atoms. In the third Al site, Al(3) is bonded in a 6-coordinate geometry to two equivalent U(1), two equivalent U(2), two equivalent Fe(1), two equivalent Al(1), and four equivalent Si(1) atoms. In the fourth Al site, Al(4) is bonded in a 10-coordinate geometry to two equivalent U(1), two equivalent U(2), two equivalent Fe(2), two equivalent Al(2), and four equivalent Si(2) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one U(1), two equivalent U(2), three equivalent Fe(1), one Al(1), and two equivalent Al(3) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent U(1), two equivalent U(2), one Fe(1), one Fe(2), one Al(2), and two equivalent Al(4) atoms. In the third Si site, Si(3) is bonded to four equivalent U(2), four equivalent Al(1), and four equivalent Al(2) atoms to form face-sharing SiU4Al8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_U6Al8Fe5Si9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.104
_cell_length_b   11.104
_cell_length_c   11.104
_cell_angle_alpha   158.694
_cell_angle_beta   113.383
_cell_angle_gamma   70.820
_symmetry_Int_Tables_number   1
_cell_volume   453.071
_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  0.872  0.872  0.000  1.0
  U  U1  1  0.128  0.128  0.000  1.0
  U  U2  1  0.189  0.875  0.314  1.0
  U  U3  1  0.439  0.125  0.314  1.0
  U  U4  1  0.561  0.875  0.686  1.0
  U  U5  1  0.811  0.125  0.686  1.0
  Al  Al6  1  0.385  0.385  0.000  1.0
  Al  Al7  1  0.615  0.615  0.000  1.0
  Al  Al8  1  0.336  0.500  0.836  1.0
  Al  Al9  1  0.664  0.500  0.164  1.0
  Al  Al10  1  0.735  0.235  0.500  1.0
  Al  Al11  1  0.265  0.765  0.500  1.0
  Al  Al12  1  0.149  0.000  0.149  1.0
  Al  Al13  1  0.851  0.000  0.851  1.0
  Fe  Fe14  1  0.970  0.286  0.685  1.0
  Fe  Fe15  1  0.399  0.714  0.685  1.0
  Fe  Fe16  1  0.601  0.286  0.315  1.0
  Fe  Fe17  1  0.030  0.714  0.315  1.0
  Fe  Fe18  1  0.000  0.500  0.500  1.0
  Si  Si19  1  0.868  0.738  0.130  1.0
  Si  Si20  1  0.392  0.262  0.130  1.0
  Si  Si21  1  0.608  0.738  0.870  1.0
  Si  Si22  1  0.132  0.262  0.870  1.0
  Si  Si23  1  0.066  0.411  0.655  1.0
  Si  Si24  1  0.243  0.589  0.655  1.0
  Si  Si25  1  0.757  0.411  0.345  1.0
  Si  Si26  1  0.934  0.589  0.345  1.0
  Si  Si27  1  0.500  0.000  0.500  1.0
[/CIF]
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The compound described by U6Fe5Al8Si9 crystallizes in the orthorhombic Immm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 12-coordinate geometry to two equivalent Fe(2), two equivalent Al(3), two equivalent Al(4), two equivalent Si(1), and four equivalent Si(2) atoms. In the second U site, U(2) is bonded in a 14-coordinate geometry to three equivalent Fe(1), one Al(3), one Al(4), two equivalent Al(1), two equivalent Al(2), one Si(3), two equivalent Si(1), and two equivalent Si(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(2) is bonded to four equivalent U(1), four equivalent Al(4), and four equivalent Si(2) atoms to form distorted face-sharing FeU4Al4Si4 cuboctahedra. In the second Fe site, Fe(1) is bonded in a 8-coordinate geometry to three equivalent U(2), one Al(3), one Si(2), and three equivalent Si(1) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to four equivalent U(2), two equivalent Al(2), two equivalent Al(3), two equivalent Si(1), and two equivalent Si(3) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to four equivalent U(2), two equivalent Al(1), two equivalent Al(4), two equivalent Si(2), and two equivalent Si(3) atoms. In the third Al site, Al(3) is bonded in a 6-coordinate geometry to two equivalent U(1), two equivalent U(2), two equivalent Fe(1), two equivalent Al(1), and four equivalent Si(1) atoms. In the fourth Al site, Al(4) is bonded in a 10-coordinate geometry to two equivalent U(1), two equivalent U(2), two equivalent Fe(2), two equivalent Al(2), and four equivalent Si(2) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one U(1), two equivalent U(2), three equivalent Fe(1), one Al(1), and two equivalent Al(3) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent U(1), two equivalent U(2), one Fe(1), one Fe(2), one Al(2), and two equivalent Al(4) atoms. In the third Si site, Si(3) is bonded to four equivalent U(2), four equivalent Al(1), and four equivalent Al(2) atoms to form face-sharing SiU4Al8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_U6Al8Fe5Si9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.104
_cell_length_b   11.104
_cell_length_c   11.104
_cell_angle_alpha   158.694
_cell_angle_beta   113.383
_cell_angle_gamma   70.820
_symmetry_Int_Tables_number   1
_cell_volume   453.071
_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  0.872  0.872  0.000  1.0
  U  U1  1  0.128  0.128  0.000  1.0
  U  U2  1  0.189  0.875  0.314  1.0
  U  U3  1  0.439  0.125  0.314  1.0
  U  U4  1  0.561  0.875  0.686  1.0
  U  U5  1  0.811  0.125  0.686  1.0
  Al  Al6  1  0.385  0.385  0.000  1.0
  Al  Al7  1  0.615  0.615  0.000  1.0
  Al  Al8  1  0.336  0.500  0.836  1.0
  Al  Al9  1  0.664  0.500  0.164  1.0
  Al  Al10  1  0.735  0.235  0.500  1.0
  Al  Al11  1  0.265  0.765  0.500  1.0
  Al  Al12  1  0.149  0.000  0.149  1.0
  Al  Al13  1  0.851  0.000  0.851  1.0
  Fe  Fe14  1  0.970  0.286  0.685  1.0
  Fe  Fe15  1  0.399  0.714  0.685  1.0
  Fe  Fe16  1  0.601  0.286  0.315  1.0
  Fe  Fe17  1  0.030  0.714  0.315  1.0
  Fe  Fe18  1  0.000  0.500  0.500  1.0
  Si  Si19  1  0.868  0.738  0.130  1.0
  Si  Si20  1  0.392  0.262  0.130  1.0
  Si  Si21  1  0.608  0.738  0.870  1.0
  Si  Si22  1  0.132  0.262  0.870  1.0
  Si  Si23  1  0.066  0.411  0.655  1.0
  Si  Si24  1  0.243  0.589  0.655  1.0
  Si  Si25  1  0.757  0.411  0.345  1.0
  Si  Si26  1  0.934  0.589  0.345  1.0
  Si  Si27  1  0.500  0.000  0.500  1.0
[/CIF]
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