The material described by YIr2Si crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 9-coordinate geometry to one Y(2) and nine equivalent Ir(1) atoms. In the second Y site, Y(2) is bonded in a 20-coordinate geometry to two equivalent Y(1), twelve equivalent Ir(1), three equivalent Si(1), and three equivalent Si(2) atoms. Ir(1) is bonded in a 12-coordinate geometry to two equivalent Y(2), three equivalent Y(1), four equivalent Ir(1), one Si(1), one Si(2), and one Si(3) atom. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 6-coordinate geometry to three equivalent Y(2) and six equivalent Ir(1) atoms. In the second Si site, Si(2) is bonded in a 6-coordinate geometry to three equivalent Y(2) and six equivalent Ir(1) atoms. In the third Si site, Si(3) is bonded in a distorted cuboctahedral geometry to six equivalent Ir(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_YSiIr2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.582
_cell_length_b   5.582
_cell_length_c   15.196
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   409.996
_cell_formula_units_Z   6
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
  Y  Y0  1  0.333  0.667  0.539  1.0
  Y  Y1  1  0.667  0.333  0.461  1.0
  Y  Y2  1  0.667  0.333  0.039  1.0
  Y  Y3  1  0.333  0.667  0.961  1.0
  Y  Y4  1  0.333  0.667  0.750  1.0
  Y  Y5  1  0.667  0.333  0.250  1.0
  Si  Si6  1  0.000  0.000  0.250  1.0
  Si  Si7  1  0.000  0.000  0.750  1.0
  Si  Si8  1  0.333  0.667  0.250  1.0
  Si  Si9  1  0.667  0.333  0.750  1.0
  Si  Si10  1  0.000  0.000  0.000  1.0
  Si  Si11  1  0.000  0.000  0.500  1.0
  Ir  Ir12  1  0.167  0.335  0.131  1.0
  Ir  Ir13  1  0.833  0.665  0.869  1.0
  Ir  Ir14  1  0.665  0.833  0.131  1.0
  Ir  Ir15  1  0.833  0.665  0.631  1.0
  Ir  Ir16  1  0.335  0.167  0.869  1.0
  Ir  Ir17  1  0.167  0.335  0.369  1.0
  Ir  Ir18  1  0.167  0.833  0.131  1.0
  Ir  Ir19  1  0.335  0.167  0.631  1.0
  Ir  Ir20  1  0.833  0.167  0.869  1.0
  Ir  Ir21  1  0.665  0.833  0.369  1.0
  Ir  Ir22  1  0.833  0.167  0.631  1.0
  Ir  Ir23  1  0.167  0.833  0.369  1.0
[/CIF]
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The material described by YIr2Si crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 9-coordinate geometry to one Y(2) and nine equivalent Ir(1) atoms. In the second Y site, Y(2) is bonded in a 20-coordinate geometry to two equivalent Y(1), twelve equivalent Ir(1), three equivalent Si(1), and three equivalent Si(2) atoms. Ir(1) is bonded in a 12-coordinate geometry to two equivalent Y(2), three equivalent Y(1), four equivalent Ir(1), one Si(1), one Si(2), and one Si(3) atom. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 6-coordinate geometry to three equivalent Y(2) and six equivalent Ir(1) atoms. In the second Si site, Si(2) is bonded in a 6-coordinate geometry to three equivalent Y(2) and six equivalent Ir(1) atoms. In the third Si site, Si(3) is bonded in a distorted cuboctahedral geometry to six equivalent Ir(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_YSiIr2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.582
_cell_length_b   5.582
_cell_length_c   15.196
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   409.996
_cell_formula_units_Z   6
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
  Y  Y0  1  0.333  0.667  0.539  1.0
  Y  Y1  1  0.667  0.333  0.461  1.0
  Y  Y2  1  0.667  0.333  0.039  1.0
  Y  Y3  1  0.333  0.667  0.961  1.0
  Y  Y4  1  0.333  0.667  0.750  1.0
  Y  Y5  1  0.667  0.333  0.250  1.0
  Si  Si6  1  0.000  0.000  0.250  1.0
  Si  Si7  1  0.000  0.000  0.750  1.0
  Si  Si8  1  0.333  0.667  0.250  1.0
  Si  Si9  1  0.667  0.333  0.750  1.0
  Si  Si10  1  0.000  0.000  0.000  1.0
  Si  Si11  1  0.000  0.000  0.500  1.0
  Ir  Ir12  1  0.167  0.335  0.131  1.0
  Ir  Ir13  1  0.833  0.665  0.869  1.0
  Ir  Ir14  1  0.665  0.833  0.131  1.0
  Ir  Ir15  1  0.833  0.665  0.631  1.0
  Ir  Ir16  1  0.335  0.167  0.869  1.0
  Ir  Ir17  1  0.167  0.335  0.369  1.0
  Ir  Ir18  1  0.167  0.833  0.131  1.0
  Ir  Ir19  1  0.335  0.167  0.631  1.0
  Ir  Ir20  1  0.833  0.167  0.869  1.0
  Ir  Ir21  1  0.665  0.833  0.369  1.0
  Ir  Ir22  1  0.833  0.167  0.631  1.0
  Ir  Ir23  1  0.167  0.833  0.369  1.0
[/CIF]
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