The crystal structure described by Cu3Al is beta Cu3Ti structured and crystallizes in the orthorhombic Pmmn space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to eight equivalent Cu(2) and four equivalent Al(1) atoms to form distorted CuAl4Cu8 cuboctahedra that share corners with two equivalent Cu(1)Al4Cu8 cuboctahedra, corners with eight equivalent Cu(2)Al4Cu8 cuboctahedra, corners with eight equivalent Al(1)Cu12 cuboctahedra, edges with six equivalent Cu(1)Al4Cu8 cuboctahedra, edges with twelve equivalent Cu(2)Al4Cu8 cuboctahedra, faces with six equivalent Cu(1)Al4Cu8 cuboctahedra, faces with six equivalent Al(1)Cu12 cuboctahedra, and faces with eight equivalent Cu(2)Al4Cu8 cuboctahedra. In the second Cu site, Cu(2) is bonded to four equivalent Cu(1), four equivalent Cu(2), and four equivalent Al(1) atoms to form CuAl4Cu8 cuboctahedra that share corners with four equivalent Cu(1)Al4Cu8 cuboctahedra, corners with four equivalent Al(1)Cu12 cuboctahedra, corners with ten equivalent Cu(2)Al4Cu8 cuboctahedra, edges with six equivalent Cu(1)Al4Cu8 cuboctahedra, edges with six equivalent Cu(2)Al4Cu8 cuboctahedra, edges with six equivalent Al(1)Cu12 cuboctahedra, faces with four equivalent Cu(1)Al4Cu8 cuboctahedra, faces with four equivalent Al(1)Cu12 cuboctahedra, and faces with twelve equivalent Cu(2)Al4Cu8 cuboctahedra. Al(1) is bonded to four equivalent Cu(1) and eight equivalent Cu(2) atoms to form AlCu12 cuboctahedra that share corners with two equivalent Al(1)Cu12 cuboctahedra, corners with eight equivalent Cu(1)Al4Cu8 cuboctahedra, corners with eight equivalent Cu(2)Al4Cu8 cuboctahedra, edges with six equivalent Al(1)Cu12 cuboctahedra, edges with twelve equivalent Cu(2)Al4Cu8 cuboctahedra, faces with six equivalent Cu(1)Al4Cu8 cuboctahedra, faces with six equivalent Al(1)Cu12 cuboctahedra, and faces with eight equivalent Cu(2)Al4Cu8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlCu3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.173
_cell_length_b   4.512
_cell_length_c   5.107
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   96.141
_cell_formula_units_Z   2
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
  Al  Al0  1  0.000  0.005  0.000  1.0
  Al  Al1  1  0.500  0.328  0.500  1.0
  Cu  Cu2  1  0.000  0.004  0.500  1.0
  Cu  Cu3  1  0.500  0.329  0.000  1.0
  Cu  Cu4  1  0.000  0.506  0.251  1.0
  Cu  Cu5  1  0.000  0.506  0.749  1.0
  Cu  Cu6  1  0.500  0.827  0.249  1.0
  Cu  Cu7  1  0.500  0.827  0.751  1.0
[/CIF]
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The crystal structure described by Cu3Al is beta Cu3Ti structured and crystallizes in the orthorhombic Pmmn space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to eight equivalent Cu(2) and four equivalent Al(1) atoms to form distorted CuAl4Cu8 cuboctahedra that share corners with two equivalent Cu(1)Al4Cu8 cuboctahedra, corners with eight equivalent Cu(2)Al4Cu8 cuboctahedra, corners with eight equivalent Al(1)Cu12 cuboctahedra, edges with six equivalent Cu(1)Al4Cu8 cuboctahedra, edges with twelve equivalent Cu(2)Al4Cu8 cuboctahedra, faces with six equivalent Cu(1)Al4Cu8 cuboctahedra, faces with six equivalent Al(1)Cu12 cuboctahedra, and faces with eight equivalent Cu(2)Al4Cu8 cuboctahedra. In the second Cu site, Cu(2) is bonded to four equivalent Cu(1), four equivalent Cu(2), and four equivalent Al(1) atoms to form CuAl4Cu8 cuboctahedra that share corners with four equivalent Cu(1)Al4Cu8 cuboctahedra, corners with four equivalent Al(1)Cu12 cuboctahedra, corners with ten equivalent Cu(2)Al4Cu8 cuboctahedra, edges with six equivalent Cu(1)Al4Cu8 cuboctahedra, edges with six equivalent Cu(2)Al4Cu8 cuboctahedra, edges with six equivalent Al(1)Cu12 cuboctahedra, faces with four equivalent Cu(1)Al4Cu8 cuboctahedra, faces with four equivalent Al(1)Cu12 cuboctahedra, and faces with twelve equivalent Cu(2)Al4Cu8 cuboctahedra. Al(1) is bonded to four equivalent Cu(1) and eight equivalent Cu(2) atoms to form AlCu12 cuboctahedra that share corners with two equivalent Al(1)Cu12 cuboctahedra, corners with eight equivalent Cu(1)Al4Cu8 cuboctahedra, corners with eight equivalent Cu(2)Al4Cu8 cuboctahedra, edges with six equivalent Al(1)Cu12 cuboctahedra, edges with twelve equivalent Cu(2)Al4Cu8 cuboctahedra, faces with six equivalent Cu(1)Al4Cu8 cuboctahedra, faces with six equivalent Al(1)Cu12 cuboctahedra, and faces with eight equivalent Cu(2)Al4Cu8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_AlCu3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.173
_cell_length_b   4.512
_cell_length_c   5.107
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   96.141
_cell_formula_units_Z   2
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
  Al  Al0  1  0.000  0.005  0.000  1.0
  Al  Al1  1  0.500  0.328  0.500  1.0
  Cu  Cu2  1  0.000  0.004  0.500  1.0
  Cu  Cu3  1  0.500  0.329  0.000  1.0
  Cu  Cu4  1  0.000  0.506  0.251  1.0
  Cu  Cu5  1  0.000  0.506  0.749  1.0
  Cu  Cu6  1  0.500  0.827  0.249  1.0
  Cu  Cu7  1  0.500  0.827  0.751  1.0
[/CIF]
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