The material structure described by Er(Fe2Al)4 crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), eight equivalent Fe(2), and four equivalent Al(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Er(1), two equivalent Fe(1), four equivalent Fe(2), and four equivalent Al(1) atoms to form a mixture of distorted corner, face, and edge-sharing FeEr2Al4Fe6 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Er(1), two equivalent Fe(2), four equivalent Fe(1), and four equivalent Al(1) atoms to form a mixture of distorted corner, face, and edge-sharing FeEr2Al4Fe6 cuboctahedra. Al(1) is bonded in a 10-coordinate geometry to one Er(1), four equivalent Fe(1), four equivalent Fe(2), and one Al(1) atom. is represented by the CIF file [CIF]
data_Er(AlFe2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.949
_cell_length_b   6.491
_cell_length_c   6.491
_cell_angle_alpha   81.645
_cell_angle_beta   67.593
_cell_angle_gamma   67.593
_symmetry_Int_Tables_number   1
_cell_volume   178.209
_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  0.000  0.000  0.000  1.0
  Al  Al1  1  0.345  0.655  0.655  1.0
  Al  Al2  1  0.655  0.345  0.345  1.0
  Al  Al3  1  0.000  0.345  0.655  1.0
  Al  Al4  1  0.000  0.655  0.345  1.0
  Fe  Fe5  1  0.500  0.000  0.500  1.0
  Fe  Fe6  1  0.000  0.000  0.500  1.0
  Fe  Fe7  1  0.000  0.500  0.000  1.0
  Fe  Fe8  1  0.500  0.500  0.000  1.0
  Fe  Fe9  1  0.270  0.230  0.230  1.0
  Fe  Fe10  1  0.730  0.770  0.770  1.0
  Fe  Fe11  1  0.500  0.770  0.230  1.0
  Fe  Fe12  1  0.500  0.230  0.770  1.0
[/CIF]
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The material structure described by Er(Fe2Al)4 crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), eight equivalent Fe(2), and four equivalent Al(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Er(1), two equivalent Fe(1), four equivalent Fe(2), and four equivalent Al(1) atoms to form a mixture of distorted corner, face, and edge-sharing FeEr2Al4Fe6 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Er(1), two equivalent Fe(2), four equivalent Fe(1), and four equivalent Al(1) atoms to form a mixture of distorted corner, face, and edge-sharing FeEr2Al4Fe6 cuboctahedra. Al(1) is bonded in a 10-coordinate geometry to one Er(1), four equivalent Fe(1), four equivalent Fe(2), and one Al(1) atom. is represented by the CIF file [CIF]
data_Er(AlFe2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.949
_cell_length_b   6.491
_cell_length_c   6.491
_cell_angle_alpha   81.645
_cell_angle_beta   67.593
_cell_angle_gamma   67.593
_symmetry_Int_Tables_number   1
_cell_volume   178.209
_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  0.000  0.000  0.000  1.0
  Al  Al1  1  0.345  0.655  0.655  1.0
  Al  Al2  1  0.655  0.345  0.345  1.0
  Al  Al3  1  0.000  0.345  0.655  1.0
  Al  Al4  1  0.000  0.655  0.345  1.0
  Fe  Fe5  1  0.500  0.000  0.500  1.0
  Fe  Fe6  1  0.000  0.000  0.500  1.0
  Fe  Fe7  1  0.000  0.500  0.000  1.0
  Fe  Fe8  1  0.500  0.500  0.000  1.0
  Fe  Fe9  1  0.270  0.230  0.230  1.0
  Fe  Fe10  1  0.730  0.770  0.770  1.0
  Fe  Fe11  1  0.500  0.770  0.230  1.0
  Fe  Fe12  1  0.500  0.230  0.770  1.0
[/CIF]
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