The material structure described by ErFe4Al8 crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), four equivalent Al(1), and eight equivalent Al(2) atoms. Fe(1) is bonded in a 12-coordinate geometry to two equivalent Er(1), two equivalent Fe(1), four equivalent Al(1), and four equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Er(1), four equivalent Fe(1), one Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to two equivalent Er(1), four equivalent Fe(1), two equivalent Al(2), and four equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_Er(Al2Fe)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.621
_cell_length_b   6.621
_cell_length_c   6.623
_cell_angle_alpha   98.134
_cell_angle_beta   98.134
_cell_angle_gamma   135.792
_symmetry_Int_Tables_number   1
_cell_volume   187.608
_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  0.659  1.000  0.659  1.0
  Al  Al2  1  1.000  0.659  0.659  1.0
  Al  Al3  1  0.000  0.341  0.341  1.0
  Al  Al4  1  0.341  0.000  0.341  1.0
  Al  Al5  1  0.721  0.500  0.221  1.0
  Al  Al6  1  0.500  0.721  0.221  1.0
  Al  Al7  1  0.500  0.279  0.779  1.0
  Al  Al8  1  0.279  0.500  0.779  1.0
  Fe  Fe9  1  0.500  0.500  0.500  1.0
  Fe  Fe10  1  1.000  1.000  0.500  1.0
  Fe  Fe11  1  0.500  0.000  1.000  1.0
  Fe  Fe12  1  1.000  0.500  1.000  1.0
[/CIF]
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The material structure described by ErFe4Al8 crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), four equivalent Al(1), and eight equivalent Al(2) atoms. Fe(1) is bonded in a 12-coordinate geometry to two equivalent Er(1), two equivalent Fe(1), four equivalent Al(1), and four equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Er(1), four equivalent Fe(1), one Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to two equivalent Er(1), four equivalent Fe(1), two equivalent Al(2), and four equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_Er(Al2Fe)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.621
_cell_length_b   6.621
_cell_length_c   6.623
_cell_angle_alpha   98.134
_cell_angle_beta   98.134
_cell_angle_gamma   135.792
_symmetry_Int_Tables_number   1
_cell_volume   187.608
_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  0.659  1.000  0.659  1.0
  Al  Al2  1  1.000  0.659  0.659  1.0
  Al  Al3  1  0.000  0.341  0.341  1.0
  Al  Al4  1  0.341  0.000  0.341  1.0
  Al  Al5  1  0.721  0.500  0.221  1.0
  Al  Al6  1  0.500  0.721  0.221  1.0
  Al  Al7  1  0.500  0.279  0.779  1.0
  Al  Al8  1  0.279  0.500  0.779  1.0
  Fe  Fe9  1  0.500  0.500  0.500  1.0
  Fe  Fe10  1  1.000  1.000  0.500  1.0
  Fe  Fe11  1  0.500  0.000  1.000  1.0
  Fe  Fe12  1  1.000  0.500  1.000  1.0
[/CIF]
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