The compound described by Er7IrI12 is trigonal omega-derived structured and crystallizes in the trigonal R-3 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to one Ir(1), two equivalent I(2), and three equivalent I(1) atoms to form distorted ErIrI5 octahedra that share corners with three equivalent Er(1)IrI5 octahedra,  an edgeedge with one Er(2)I6 octahedra, and edges with five equivalent Er(1)IrI5 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the second Er site, Er(2) is bonded to six equivalent I(2) atoms to form edge-sharing ErI6 octahedra. Ir(1) is bonded in an octahedral geometry to six equivalent Er(1) atoms. There are two inequivalent I sites. In the first I site, I(1) is bonded in a distorted T-shaped geometry to three equivalent Er(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to one Er(2) and two equivalent Er(1) atoms. is represented by the CIF card [CIF]
data_Er7IrI12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.661
_cell_length_b   9.661
_cell_length_c   9.661
_cell_angle_alpha   106.903
_cell_angle_beta   106.903
_cell_angle_gamma   106.903
_symmetry_Int_Tables_number   1
_cell_volume   753.020
_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
  Er  Er0  1  0.094  0.023  0.295  1.0
  Er  Er1  1  0.295  0.094  0.023  1.0
  Er  Er2  1  0.023  0.295  0.094  1.0
  Er  Er3  1  0.906  0.977  0.705  1.0
  Er  Er4  1  0.705  0.906  0.977  1.0
  Er  Er5  1  0.977  0.705  0.906  1.0
  Er  Er6  1  0.500  0.500  0.500  1.0
  Ir  Ir7  1  0.000  0.000  0.000  1.0
  I  I8  1  0.070  0.675  0.226  1.0
  I  I9  1  0.226  0.070  0.675  1.0
  I  I10  1  0.675  0.226  0.070  1.0
  I  I11  1  0.930  0.325  0.774  1.0
  I  I12  1  0.774  0.930  0.325  1.0
  I  I13  1  0.325  0.774  0.930  1.0
  I  I14  1  0.466  0.163  0.389  1.0
  I  I15  1  0.389  0.466  0.163  1.0
  I  I16  1  0.163  0.389  0.466  1.0
  I  I17  1  0.534  0.837  0.611  1.0
  I  I18  1  0.611  0.534  0.837  1.0
  I  I19  1  0.837  0.611  0.534  1.0
[/CIF]
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The compound described by Er7IrI12 is trigonal omega-derived structured and crystallizes in the trigonal R-3 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to one Ir(1), two equivalent I(2), and three equivalent I(1) atoms to form distorted ErIrI5 octahedra that share corners with three equivalent Er(1)IrI5 octahedra,  an edgeedge with one Er(2)I6 octahedra, and edges with five equivalent Er(1)IrI5 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the second Er site, Er(2) is bonded to six equivalent I(2) atoms to form edge-sharing ErI6 octahedra. Ir(1) is bonded in an octahedral geometry to six equivalent Er(1) atoms. There are two inequivalent I sites. In the first I site, I(1) is bonded in a distorted T-shaped geometry to three equivalent Er(1) atoms. In the second I site, I(2) is bonded in a distorted T-shaped geometry to one Er(2) and two equivalent Er(1) atoms. is represented by the CIF card [CIF]
data_Er7IrI12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.661
_cell_length_b   9.661
_cell_length_c   9.661
_cell_angle_alpha   106.903
_cell_angle_beta   106.903
_cell_angle_gamma   106.903
_symmetry_Int_Tables_number   1
_cell_volume   753.020
_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
  Er  Er0  1  0.094  0.023  0.295  1.0
  Er  Er1  1  0.295  0.094  0.023  1.0
  Er  Er2  1  0.023  0.295  0.094  1.0
  Er  Er3  1  0.906  0.977  0.705  1.0
  Er  Er4  1  0.705  0.906  0.977  1.0
  Er  Er5  1  0.977  0.705  0.906  1.0
  Er  Er6  1  0.500  0.500  0.500  1.0
  Ir  Ir7  1  0.000  0.000  0.000  1.0
  I  I8  1  0.070  0.675  0.226  1.0
  I  I9  1  0.226  0.070  0.675  1.0
  I  I10  1  0.675  0.226  0.070  1.0
  I  I11  1  0.930  0.325  0.774  1.0
  I  I12  1  0.774  0.930  0.325  1.0
  I  I13  1  0.325  0.774  0.930  1.0
  I  I14  1  0.466  0.163  0.389  1.0
  I  I15  1  0.389  0.466  0.163  1.0
  I  I16  1  0.163  0.389  0.466  1.0
  I  I17  1  0.534  0.837  0.611  1.0
  I  I18  1  0.611  0.534  0.837  1.0
  I  I19  1  0.837  0.611  0.534  1.0
[/CIF]
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