The compound described by Ir4Si5 crystallizes in the monoclinic P2_1/m space group. There are four inequivalent Ir sites. In the first Ir site, Ir(1) is bonded in a 7-coordinate geometry to one Si(3), three equivalent Si(4), and three equivalent Si(5) atoms. In the second Ir site, Ir(2) is bonded in a 6-coordinate geometry to one Si(2), one Si(3), two equivalent Si(1), and two equivalent Si(4) atoms. In the third Ir site, Ir(3) is bonded in a 6-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. In the fourth Ir site, Ir(4) is bonded in a 7-coordinate geometry to one Si(1), one Si(4), one Si(5), two equivalent Si(2), and two equivalent Si(3) atoms. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded in a 6-coordinate geometry to one Ir(4), two equivalent Ir(2), and three equivalent Ir(3) atoms. In the second Si site, Si(2) is bonded in a 6-coordinate geometry to one Ir(2), two equivalent Ir(4), and three equivalent Ir(3) atoms. In the third Si site, Si(3) is bonded in a 4-coordinate geometry to one Ir(1), one Ir(2), and two equivalent Ir(4) atoms. In the fourth Si site, Si(4) is bonded in a 6-coordinate geometry to one Ir(4), two equivalent Ir(2), and three equivalent Ir(1) atoms. In the fifth Si site, Si(5) is bonded to one Ir(4) and three equivalent Ir(1) atoms to form a mixture of distorted corner and edge-sharing SiIr4 tetrahedra. is represented by the CIF file [CIF]
data_Si5Ir4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.653
_cell_length_b   5.943
_cell_length_c   12.451
_cell_angle_alpha   100.034
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   266.183
_cell_formula_units_Z   2
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
  Si  Si0  1  0.250  0.643  0.637  1.0
  Si  Si1  1  0.750  0.357  0.363  1.0
  Si  Si2  1  0.250  0.890  0.424  1.0
  Si  Si3  1  0.750  0.110  0.576  1.0
  Si  Si4  1  0.250  0.472  0.225  1.0
  Si  Si5  1  0.750  0.528  0.775  1.0
  Si  Si6  1  0.750  0.978  0.141  1.0
  Si  Si7  1  0.250  0.022  0.859  1.0
  Si  Si8  1  0.250  0.491  0.922  1.0
  Si  Si9  1  0.750  0.509  0.078  1.0
  Ir  Ir10  1  0.250  0.219  0.049  1.0
  Ir  Ir11  1  0.750  0.781  0.951  1.0
  Ir  Ir12  1  0.250  0.107  0.274  1.0
  Ir  Ir13  1  0.750  0.893  0.726  1.0
  Ir  Ir14  1  0.250  0.300  0.502  1.0
  Ir  Ir15  1  0.750  0.700  0.498  1.0
  Ir  Ir16  1  0.250  0.290  0.731  1.0
  Ir  Ir17  1  0.750  0.710  0.269  1.0
[/CIF]
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The compound described by Ir4Si5 crystallizes in the monoclinic P2_1/m space group. There are four inequivalent Ir sites. In the first Ir site, Ir(1) is bonded in a 7-coordinate geometry to one Si(3), three equivalent Si(4), and three equivalent Si(5) atoms. In the second Ir site, Ir(2) is bonded in a 6-coordinate geometry to one Si(2), one Si(3), two equivalent Si(1), and two equivalent Si(4) atoms. In the third Ir site, Ir(3) is bonded in a 6-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. In the fourth Ir site, Ir(4) is bonded in a 7-coordinate geometry to one Si(1), one Si(4), one Si(5), two equivalent Si(2), and two equivalent Si(3) atoms. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded in a 6-coordinate geometry to one Ir(4), two equivalent Ir(2), and three equivalent Ir(3) atoms. In the second Si site, Si(2) is bonded in a 6-coordinate geometry to one Ir(2), two equivalent Ir(4), and three equivalent Ir(3) atoms. In the third Si site, Si(3) is bonded in a 4-coordinate geometry to one Ir(1), one Ir(2), and two equivalent Ir(4) atoms. In the fourth Si site, Si(4) is bonded in a 6-coordinate geometry to one Ir(4), two equivalent Ir(2), and three equivalent Ir(1) atoms. In the fifth Si site, Si(5) is bonded to one Ir(4) and three equivalent Ir(1) atoms to form a mixture of distorted corner and edge-sharing SiIr4 tetrahedra. is represented by the CIF file [CIF]
data_Si5Ir4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.653
_cell_length_b   5.943
_cell_length_c   12.451
_cell_angle_alpha   100.034
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   266.183
_cell_formula_units_Z   2
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
  Si  Si0  1  0.250  0.643  0.637  1.0
  Si  Si1  1  0.750  0.357  0.363  1.0
  Si  Si2  1  0.250  0.890  0.424  1.0
  Si  Si3  1  0.750  0.110  0.576  1.0
  Si  Si4  1  0.250  0.472  0.225  1.0
  Si  Si5  1  0.750  0.528  0.775  1.0
  Si  Si6  1  0.750  0.978  0.141  1.0
  Si  Si7  1  0.250  0.022  0.859  1.0
  Si  Si8  1  0.250  0.491  0.922  1.0
  Si  Si9  1  0.750  0.509  0.078  1.0
  Ir  Ir10  1  0.250  0.219  0.049  1.0
  Ir  Ir11  1  0.750  0.781  0.951  1.0
  Ir  Ir12  1  0.250  0.107  0.274  1.0
  Ir  Ir13  1  0.750  0.893  0.726  1.0
  Ir  Ir14  1  0.250  0.300  0.502  1.0
  Ir  Ir15  1  0.750  0.700  0.498  1.0
  Ir  Ir16  1  0.250  0.290  0.731  1.0
  Ir  Ir17  1  0.750  0.710  0.269  1.0
[/CIF]
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