The compound described by Eu(CuAl2)4 crystallizes in the tetragonal I4/mmm space group. Eu(1) is bonded in a 20-coordinate geometry to eight equivalent Cu(1), four equivalent Al(1), and eight equivalent Al(2) atoms. Cu(1) is bonded to two equivalent Eu(1), two equivalent Cu(1), four equivalent Al(1), and four equivalent Al(2) atoms to form a mixture of distorted corner, edge, and face-sharing CuEu2Al8Cu2 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Eu(1), four equivalent Cu(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 Eu(1), four equivalent Cu(1), two equivalent Al(2), and four equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Eu(Al2Cu)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.721
_cell_length_b   6.721
_cell_length_c   6.719
_cell_angle_alpha   98.322
_cell_angle_beta   98.322
_cell_angle_gamma   135.292
_symmetry_Int_Tables_number   1
_cell_volume   197.427
_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
  Eu  Eu0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.349  0.349  1.0
  Al  Al2  1  1.000  0.651  0.651  1.0
  Al  Al3  1  0.651  1.000  0.651  1.0
  Al  Al4  1  0.349  0.000  0.349  1.0
  Al  Al5  1  0.500  0.278  0.778  1.0
  Al  Al6  1  0.500  0.722  0.222  1.0
  Al  Al7  1  0.722  0.500  0.222  1.0
  Al  Al8  1  0.278  0.500  0.778  1.0
  Cu  Cu9  1  0.000  0.000  0.500  1.0
  Cu  Cu10  1  0.500  0.500  0.500  1.0
  Cu  Cu11  1  0.500  0.000  0.000  1.0
  Cu  Cu12  1  0.000  0.500  0.000  1.0
[/CIF]
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The compound described by Eu(CuAl2)4 crystallizes in the tetragonal I4/mmm space group. Eu(1) is bonded in a 20-coordinate geometry to eight equivalent Cu(1), four equivalent Al(1), and eight equivalent Al(2) atoms. Cu(1) is bonded to two equivalent Eu(1), two equivalent Cu(1), four equivalent Al(1), and four equivalent Al(2) atoms to form a mixture of distorted corner, edge, and face-sharing CuEu2Al8Cu2 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Eu(1), four equivalent Cu(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 Eu(1), four equivalent Cu(1), two equivalent Al(2), and four equivalent Al(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Eu(Al2Cu)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.721
_cell_length_b   6.721
_cell_length_c   6.719
_cell_angle_alpha   98.322
_cell_angle_beta   98.322
_cell_angle_gamma   135.292
_symmetry_Int_Tables_number   1
_cell_volume   197.427
_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
  Eu  Eu0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.349  0.349  1.0
  Al  Al2  1  1.000  0.651  0.651  1.0
  Al  Al3  1  0.651  1.000  0.651  1.0
  Al  Al4  1  0.349  0.000  0.349  1.0
  Al  Al5  1  0.500  0.278  0.778  1.0
  Al  Al6  1  0.500  0.722  0.222  1.0
  Al  Al7  1  0.722  0.500  0.222  1.0
  Al  Al8  1  0.278  0.500  0.778  1.0
  Cu  Cu9  1  0.000  0.000  0.500  1.0
  Cu  Cu10  1  0.500  0.500  0.500  1.0
  Cu  Cu11  1  0.500  0.000  0.000  1.0
  Cu  Cu12  1  0.000  0.500  0.000  1.0
[/CIF]
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