The material described by Er4Ir13Si9 crystallizes in the orthorhombic Pmmn space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 16-coordinate geometry to one Ir(3), one Ir(4), one Ir(6), one Ir(8), two equivalent Ir(1), two equivalent Ir(2), two equivalent Ir(7), two equivalent Si(3), two equivalent Si(5), and two equivalent Si(6) atoms. In the second Er site, Er(2) is bonded in a 18-coordinate geometry to two equivalent Ir(1), two equivalent Ir(3), two equivalent Ir(8), six equivalent Ir(5), two equivalent Si(1), and four equivalent Si(2) atoms. In the third Er site, Er(3) is bonded in a 16-coordinate geometry to two equivalent Ir(2), two equivalent Ir(7), six equivalent Ir(6), two equivalent Si(4), and four equivalent Si(3) atoms. There are eight inequivalent Ir sites. In the first Ir site, Ir(3) is bonded to two equivalent Er(1), two equivalent Er(2), two equivalent Si(2), and two equivalent Si(6) atoms to form a mixture of distorted corner and edge-sharing IrEr4Si4 tetrahedra. In the second Ir site, Ir(4) is bonded in a 5-coordinate geometry to two equivalent Er(1), one Si(4), and four equivalent Si(5) atoms. In the third Ir site, Ir(5) is bonded in a 6-coordinate geometry to three equivalent Er(2), one Si(1), and three equivalent Si(2) atoms. In the fourth Ir site, Ir(6) is bonded to one Er(1), three equivalent Er(3), one Si(4), and three equivalent Si(3) atoms to form a mixture of distorted corner, face, and edge-sharing IrEr4Si4 tetrahedra. In the fifth Ir site, Ir(7) is bonded in a 6-coordinate geometry to one Er(3), two equivalent Er(1), one Si(3), one Si(5), and two equivalent Si(4) atoms. In the sixth Ir site, Ir(8) is bonded in a 5-coordinate geometry to one Er(1), one Er(2), one Si(2), two equivalent Si(1), and two equivalent Si(5) atoms. In the seventh Ir site, Ir(1) is bonded in a 4-coordinate geometry to one Er(2), two equivalent Er(1), one Si(5), one Si(6), and two equivalent Si(2) atoms. In the eighth Ir site, Ir(2) is bonded in a 9-coordinate geometry to two equivalent Er(3), four equivalent Er(1), one Si(6), and two equivalent Si(3) atoms. There are six inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to two equivalent Er(2), two equivalent Ir(5), four equivalent Ir(8), and two equivalent Si(5) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Er(2), one Ir(3), one Ir(8), two equivalent Ir(1), and three equivalent Ir(5) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(3), one Ir(2), one Ir(7), and three equivalent Ir(6) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Er(3), one Ir(4), two equivalent Ir(6), and four equivalent Ir(7) atoms. In the fifth Si site, Si(5) is bonded in a 10-coordinate geometry to two equivalent Er(1), one Ir(1), one Ir(7), two equivalent Ir(4), two equivalent Ir(8), one Si(1), and one Si(5) atom. In the sixth Si site, Si(6) is bonded in a 9-coordinate geometry to four equivalent Er(1), one Ir(2), two equivalent Ir(1), and two equivalent Ir(3) atoms. is represented by the CIF file [CIF]
data_Er4Si9Ir13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.932
_cell_length_b   10.930
_cell_length_c   18.884
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   811.507
_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
  Er  Er0  1  0.500  0.691  0.208  1.0
  Er  Er1  1  0.000  0.809  0.792  1.0
  Er  Er2  1  1.000  0.191  0.792  1.0
  Er  Er3  1  0.500  0.309  0.208  1.0
  Er  Er4  1  0.500  0.000  0.519  1.0
  Er  Er5  1  1.000  0.500  0.481  1.0
  Er  Er6  1  0.500  0.500  0.022  1.0
  Er  Er7  1  1.000  0.000  0.978  1.0
  Si  Si8  1  0.000  0.000  0.397  1.0
  Si  Si9  1  0.500  0.500  0.603  1.0
  Si  Si10  1  0.500  0.318  0.415  1.0
  Si  Si11  1  1.000  0.182  0.585  1.0
  Si  Si12  1  1.000  0.818  0.585  1.0
  Si  Si13  1  0.500  0.682  0.415  1.0
  Si  Si14  1  0.000  0.688  0.080  1.0
  Si  Si15  1  0.500  0.812  0.920  1.0
  Si  Si16  1  0.500  0.188  0.920  1.0
  Si  Si17  1  0.000  0.312  0.080  1.0
  Si  Si18  1  0.500  0.000  0.102  1.0
  Si  Si19  1  0.000  0.500  0.898  1.0
  Si  Si20  1  0.500  0.374  0.729  1.0
  Si  Si21  1  1.000  0.126  0.271  1.0
  Si  Si22  1  0.000  0.874  0.271  1.0
  Si  Si23  1  0.500  0.626  0.729  1.0
  Si  Si24  1  0.500  0.000  0.732  1.0
  Si  Si25  1  0.000  0.500  0.268  1.0
  Ir  Ir26  1  0.000  0.684  0.335  1.0
  Ir  Ir27  1  0.500  0.816  0.665  1.0
  Ir  Ir28  1  0.500  0.184  0.665  1.0
  Ir  Ir29  1  0.000  0.316  0.335  1.0
  Ir  Ir30  1  0.000  0.500  0.142  1.0
  Ir  Ir31  1  0.500  0.000  0.858  1.0
  Ir  Ir32  1  0.500  0.500  0.343  1.0
  Ir  Ir33  1  1.000  0.000  0.657  1.0
  Ir  Ir34  1  1.000  0.500  0.773  1.0
  Ir  Ir35  1  0.500  0.000  0.227  1.0
  Ir  Ir36  1  0.500  0.688  0.539  1.0
  Ir  Ir37  1  0.000  0.812  0.461  1.0
  Ir  Ir38  1  1.000  0.188  0.461  1.0
  Ir  Ir39  1  0.500  0.312  0.539  1.0
  Ir  Ir40  1  0.000  0.700  0.953  1.0
  Ir  Ir41  1  0.500  0.799  0.047  1.0
  Ir  Ir42  1  0.500  0.201  0.047  1.0
  Ir  Ir43  1  1.000  0.300  0.953  1.0
  Ir  Ir44  1  0.000  0.875  0.144  1.0
  Ir  Ir45  1  0.500  0.625  0.856  1.0
  Ir  Ir46  1  0.500  0.375  0.856  1.0
  Ir  Ir47  1  0.000  0.125  0.144  1.0
  Ir  Ir48  1  0.500  0.872  0.356  1.0
  Ir  Ir49  1  1.000  0.628  0.644  1.0
  Ir  Ir50  1  1.000  0.372  0.644  1.0
  Ir  Ir51  1  0.500  0.128  0.356  1.0
[/CIF]
.
The material described by Er4Ir13Si9 crystallizes in the orthorhombic Pmmn space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 16-coordinate geometry to one Ir(3), one Ir(4), one Ir(6), one Ir(8), two equivalent Ir(1), two equivalent Ir(2), two equivalent Ir(7), two equivalent Si(3), two equivalent Si(5), and two equivalent Si(6) atoms. In the second Er site, Er(2) is bonded in a 18-coordinate geometry to two equivalent Ir(1), two equivalent Ir(3), two equivalent Ir(8), six equivalent Ir(5), two equivalent Si(1), and four equivalent Si(2) atoms. In the third Er site, Er(3) is bonded in a 16-coordinate geometry to two equivalent Ir(2), two equivalent Ir(7), six equivalent Ir(6), two equivalent Si(4), and four equivalent Si(3) atoms. There are eight inequivalent Ir sites. In the first Ir site, Ir(3) is bonded to two equivalent Er(1), two equivalent Er(2), two equivalent Si(2), and two equivalent Si(6) atoms to form a mixture of distorted corner and edge-sharing IrEr4Si4 tetrahedra. In the second Ir site, Ir(4) is bonded in a 5-coordinate geometry to two equivalent Er(1), one Si(4), and four equivalent Si(5) atoms. In the third Ir site, Ir(5) is bonded in a 6-coordinate geometry to three equivalent Er(2), one Si(1), and three equivalent Si(2) atoms. In the fourth Ir site, Ir(6) is bonded to one Er(1), three equivalent Er(3), one Si(4), and three equivalent Si(3) atoms to form a mixture of distorted corner, face, and edge-sharing IrEr4Si4 tetrahedra. In the fifth Ir site, Ir(7) is bonded in a 6-coordinate geometry to one Er(3), two equivalent Er(1), one Si(3), one Si(5), and two equivalent Si(4) atoms. In the sixth Ir site, Ir(8) is bonded in a 5-coordinate geometry to one Er(1), one Er(2), one Si(2), two equivalent Si(1), and two equivalent Si(5) atoms. In the seventh Ir site, Ir(1) is bonded in a 4-coordinate geometry to one Er(2), two equivalent Er(1), one Si(5), one Si(6), and two equivalent Si(2) atoms. In the eighth Ir site, Ir(2) is bonded in a 9-coordinate geometry to two equivalent Er(3), four equivalent Er(1), one Si(6), and two equivalent Si(3) atoms. There are six inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to two equivalent Er(2), two equivalent Ir(5), four equivalent Ir(8), and two equivalent Si(5) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Er(2), one Ir(3), one Ir(8), two equivalent Ir(1), and three equivalent Ir(5) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(3), one Ir(2), one Ir(7), and three equivalent Ir(6) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Er(3), one Ir(4), two equivalent Ir(6), and four equivalent Ir(7) atoms. In the fifth Si site, Si(5) is bonded in a 10-coordinate geometry to two equivalent Er(1), one Ir(1), one Ir(7), two equivalent Ir(4), two equivalent Ir(8), one Si(1), and one Si(5) atom. In the sixth Si site, Si(6) is bonded in a 9-coordinate geometry to four equivalent Er(1), one Ir(2), two equivalent Ir(1), and two equivalent Ir(3) atoms. is represented by the CIF file [CIF]
data_Er4Si9Ir13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.932
_cell_length_b   10.930
_cell_length_c   18.884
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   811.507
_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
  Er  Er0  1  0.500  0.691  0.208  1.0
  Er  Er1  1  0.000  0.809  0.792  1.0
  Er  Er2  1  1.000  0.191  0.792  1.0
  Er  Er3  1  0.500  0.309  0.208  1.0
  Er  Er4  1  0.500  0.000  0.519  1.0
  Er  Er5  1  1.000  0.500  0.481  1.0
  Er  Er6  1  0.500  0.500  0.022  1.0
  Er  Er7  1  1.000  0.000  0.978  1.0
  Si  Si8  1  0.000  0.000  0.397  1.0
  Si  Si9  1  0.500  0.500  0.603  1.0
  Si  Si10  1  0.500  0.318  0.415  1.0
  Si  Si11  1  1.000  0.182  0.585  1.0
  Si  Si12  1  1.000  0.818  0.585  1.0
  Si  Si13  1  0.500  0.682  0.415  1.0
  Si  Si14  1  0.000  0.688  0.080  1.0
  Si  Si15  1  0.500  0.812  0.920  1.0
  Si  Si16  1  0.500  0.188  0.920  1.0
  Si  Si17  1  0.000  0.312  0.080  1.0
  Si  Si18  1  0.500  0.000  0.102  1.0
  Si  Si19  1  0.000  0.500  0.898  1.0
  Si  Si20  1  0.500  0.374  0.729  1.0
  Si  Si21  1  1.000  0.126  0.271  1.0
  Si  Si22  1  0.000  0.874  0.271  1.0
  Si  Si23  1  0.500  0.626  0.729  1.0
  Si  Si24  1  0.500  0.000  0.732  1.0
  Si  Si25  1  0.000  0.500  0.268  1.0
  Ir  Ir26  1  0.000  0.684  0.335  1.0
  Ir  Ir27  1  0.500  0.816  0.665  1.0
  Ir  Ir28  1  0.500  0.184  0.665  1.0
  Ir  Ir29  1  0.000  0.316  0.335  1.0
  Ir  Ir30  1  0.000  0.500  0.142  1.0
  Ir  Ir31  1  0.500  0.000  0.858  1.0
  Ir  Ir32  1  0.500  0.500  0.343  1.0
  Ir  Ir33  1  1.000  0.000  0.657  1.0
  Ir  Ir34  1  1.000  0.500  0.773  1.0
  Ir  Ir35  1  0.500  0.000  0.227  1.0
  Ir  Ir36  1  0.500  0.688  0.539  1.0
  Ir  Ir37  1  0.000  0.812  0.461  1.0
  Ir  Ir38  1  1.000  0.188  0.461  1.0
  Ir  Ir39  1  0.500  0.312  0.539  1.0
  Ir  Ir40  1  0.000  0.700  0.953  1.0
  Ir  Ir41  1  0.500  0.799  0.047  1.0
  Ir  Ir42  1  0.500  0.201  0.047  1.0
  Ir  Ir43  1  1.000  0.300  0.953  1.0
  Ir  Ir44  1  0.000  0.875  0.144  1.0
  Ir  Ir45  1  0.500  0.625  0.856  1.0
  Ir  Ir46  1  0.500  0.375  0.856  1.0
  Ir  Ir47  1  0.000  0.125  0.144  1.0
  Ir  Ir48  1  0.500  0.872  0.356  1.0
  Ir  Ir49  1  1.000  0.628  0.644  1.0
  Ir  Ir50  1  1.000  0.372  0.644  1.0
  Ir  Ir51  1  0.500  0.128  0.356  1.0
[/CIF]
.