The material structure described by Ir3Si4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Ir sites. In the first Ir site, Ir(1) is bonded in a 7-coordinate geometry to one Si(1), one Si(2), two equivalent Si(4), and three equivalent Si(3) atoms. In the second Ir site, Ir(2) is bonded in a 6-coordinate geometry to one Si(4), two equivalent Si(2), and three equivalent Si(3) atoms. In the third Ir site, Ir(3) is bonded in a 7-coordinate geometry to one Si(4), three equivalent Si(1), and three equivalent Si(2) atoms. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one Ir(1) and three equivalent Ir(3) atoms to form a mixture of distorted corner and edge-sharing SiIr4 tetrahedra. In the second Si site, Si(2) is bonded in a 6-coordinate geometry to one Ir(1), two equivalent Ir(2), and three equivalent Ir(3) atoms. In the third Si site, Si(3) is bonded in a 6-coordinate geometry to three equivalent Ir(1) and three equivalent Ir(2) atoms. In the fourth Si site, Si(4) is bonded in a 4-coordinate geometry to one Ir(2), one Ir(3), and two equivalent Ir(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Si4Ir3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.704
_cell_length_b   5.818
_cell_length_c   18.929
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   407.888
_cell_formula_units_Z   4
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  0.974  0.450  1.0
  Si  Si1  1  0.750  0.026  0.550  1.0
  Si  Si2  1  0.750  0.474  0.050  1.0
  Si  Si3  1  0.250  0.526  0.950  1.0
  Si  Si4  1  0.250  0.077  0.909  1.0
  Si  Si5  1  0.750  0.923  0.091  1.0
  Si  Si6  1  0.750  0.577  0.591  1.0
  Si  Si7  1  0.250  0.423  0.409  1.0
  Si  Si8  1  0.250  0.717  0.270  1.0
  Si  Si9  1  0.750  0.283  0.730  1.0
  Si  Si10  1  0.750  0.217  0.230  1.0
  Si  Si11  1  0.250  0.783  0.770  1.0
  Si  Si12  1  0.250  0.388  0.144  1.0
  Si  Si13  1  0.750  0.612  0.856  1.0
  Si  Si14  1  0.750  0.888  0.356  1.0
  Si  Si15  1  0.250  0.112  0.644  1.0
  Ir  Ir16  1  0.250  0.394  0.826  1.0
  Ir  Ir17  1  0.750  0.606  0.174  1.0
  Ir  Ir18  1  0.750  0.894  0.674  1.0
  Ir  Ir19  1  0.250  0.106  0.326  1.0
  Ir  Ir20  1  0.250  0.499  0.676  1.0
  Ir  Ir21  1  0.750  0.501  0.324  1.0
  Ir  Ir22  1  0.750  0.999  0.824  1.0
  Ir  Ir23  1  0.250  0.001  0.176  1.0
  Ir  Ir24  1  0.250  0.304  0.531  1.0
  Ir  Ir25  1  0.750  0.696  0.469  1.0
  Ir  Ir26  1  0.750  0.804  0.969  1.0
  Ir  Ir27  1  0.250  0.196  0.031  1.0
[/CIF]
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The material structure described by Ir3Si4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Ir sites. In the first Ir site, Ir(1) is bonded in a 7-coordinate geometry to one Si(1), one Si(2), two equivalent Si(4), and three equivalent Si(3) atoms. In the second Ir site, Ir(2) is bonded in a 6-coordinate geometry to one Si(4), two equivalent Si(2), and three equivalent Si(3) atoms. In the third Ir site, Ir(3) is bonded in a 7-coordinate geometry to one Si(4), three equivalent Si(1), and three equivalent Si(2) atoms. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one Ir(1) and three equivalent Ir(3) atoms to form a mixture of distorted corner and edge-sharing SiIr4 tetrahedra. In the second Si site, Si(2) is bonded in a 6-coordinate geometry to one Ir(1), two equivalent Ir(2), and three equivalent Ir(3) atoms. In the third Si site, Si(3) is bonded in a 6-coordinate geometry to three equivalent Ir(1) and three equivalent Ir(2) atoms. In the fourth Si site, Si(4) is bonded in a 4-coordinate geometry to one Ir(2), one Ir(3), and two equivalent Ir(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Si4Ir3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.704
_cell_length_b   5.818
_cell_length_c   18.929
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   407.888
_cell_formula_units_Z   4
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  0.974  0.450  1.0
  Si  Si1  1  0.750  0.026  0.550  1.0
  Si  Si2  1  0.750  0.474  0.050  1.0
  Si  Si3  1  0.250  0.526  0.950  1.0
  Si  Si4  1  0.250  0.077  0.909  1.0
  Si  Si5  1  0.750  0.923  0.091  1.0
  Si  Si6  1  0.750  0.577  0.591  1.0
  Si  Si7  1  0.250  0.423  0.409  1.0
  Si  Si8  1  0.250  0.717  0.270  1.0
  Si  Si9  1  0.750  0.283  0.730  1.0
  Si  Si10  1  0.750  0.217  0.230  1.0
  Si  Si11  1  0.250  0.783  0.770  1.0
  Si  Si12  1  0.250  0.388  0.144  1.0
  Si  Si13  1  0.750  0.612  0.856  1.0
  Si  Si14  1  0.750  0.888  0.356  1.0
  Si  Si15  1  0.250  0.112  0.644  1.0
  Ir  Ir16  1  0.250  0.394  0.826  1.0
  Ir  Ir17  1  0.750  0.606  0.174  1.0
  Ir  Ir18  1  0.750  0.894  0.674  1.0
  Ir  Ir19  1  0.250  0.106  0.326  1.0
  Ir  Ir20  1  0.250  0.499  0.676  1.0
  Ir  Ir21  1  0.750  0.501  0.324  1.0
  Ir  Ir22  1  0.750  0.999  0.824  1.0
  Ir  Ir23  1  0.250  0.001  0.176  1.0
  Ir  Ir24  1  0.250  0.304  0.531  1.0
  Ir  Ir25  1  0.750  0.696  0.469  1.0
  Ir  Ir26  1  0.750  0.804  0.969  1.0
  Ir  Ir27  1  0.250  0.196  0.031  1.0
[/CIF]
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