The compound described by Al2Er3 crystallizes in the tetragonal P4_2/mnm space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a distorted square co-planar geometry to four equivalent Al(1) atoms. In the second Er site, Er(3) is bonded in a 6-coordinate geometry to six equivalent Al(1) atoms. In the third Er site, Er(2) is bonded in a 6-coordinate geometry to six equivalent Al(1) atoms. Al(1) is bonded in a 10-coordinate geometry to two equivalent Er(1), three equivalent Er(2), three equivalent Er(3), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er3Al2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.541
_cell_length_b   8.113
_cell_length_c   8.113
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   496.358
_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
  Er  Er0  1  0.250  0.000  0.500  1.0
  Er  Er1  1  0.750  0.000  0.500  1.0
  Er  Er2  1  0.250  0.500  0.000  1.0
  Er  Er3  1  0.750  0.500  0.000  1.0
  Er  Er4  1  0.000  0.152  0.152  1.0
  Er  Er5  1  0.500  0.348  0.652  1.0
  Er  Er6  1  0.500  0.652  0.348  1.0
  Er  Er7  1  0.000  0.848  0.848  1.0
  Er  Er8  1  0.000  0.701  0.299  1.0
  Er  Er9  1  0.500  0.201  0.201  1.0
  Er  Er10  1  0.500  0.799  0.799  1.0
  Er  Er11  1  0.000  0.299  0.701  1.0
  Al  Al12  1  0.197  0.381  0.381  1.0
  Al  Al13  1  0.697  0.119  0.881  1.0
  Al  Al14  1  0.697  0.881  0.119  1.0
  Al  Al15  1  0.197  0.619  0.619  1.0
  Al  Al16  1  0.303  0.881  0.119  1.0
  Al  Al17  1  0.303  0.119  0.881  1.0
  Al  Al18  1  0.803  0.381  0.381  1.0
  Al  Al19  1  0.803  0.619  0.619  1.0
[/CIF]
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The compound described by Al2Er3 crystallizes in the tetragonal P4_2/mnm space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a distorted square co-planar geometry to four equivalent Al(1) atoms. In the second Er site, Er(3) is bonded in a 6-coordinate geometry to six equivalent Al(1) atoms. In the third Er site, Er(2) is bonded in a 6-coordinate geometry to six equivalent Al(1) atoms. Al(1) is bonded in a 10-coordinate geometry to two equivalent Er(1), three equivalent Er(2), three equivalent Er(3), and two equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er3Al2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.541
_cell_length_b   8.113
_cell_length_c   8.113
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   496.358
_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
  Er  Er0  1  0.250  0.000  0.500  1.0
  Er  Er1  1  0.750  0.000  0.500  1.0
  Er  Er2  1  0.250  0.500  0.000  1.0
  Er  Er3  1  0.750  0.500  0.000  1.0
  Er  Er4  1  0.000  0.152  0.152  1.0
  Er  Er5  1  0.500  0.348  0.652  1.0
  Er  Er6  1  0.500  0.652  0.348  1.0
  Er  Er7  1  0.000  0.848  0.848  1.0
  Er  Er8  1  0.000  0.701  0.299  1.0
  Er  Er9  1  0.500  0.201  0.201  1.0
  Er  Er10  1  0.500  0.799  0.799  1.0
  Er  Er11  1  0.000  0.299  0.701  1.0
  Al  Al12  1  0.197  0.381  0.381  1.0
  Al  Al13  1  0.697  0.119  0.881  1.0
  Al  Al14  1  0.697  0.881  0.119  1.0
  Al  Al15  1  0.197  0.619  0.619  1.0
  Al  Al16  1  0.303  0.881  0.119  1.0
  Al  Al17  1  0.303  0.119  0.881  1.0
  Al  Al18  1  0.803  0.381  0.381  1.0
  Al  Al19  1  0.803  0.619  0.619  1.0
[/CIF]
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