The crystal structure described by Yb2CuAl3 crystallizes in the trigonal R-3m space group. Yb(1) is bonded in a 12-coordinate geometry to three equivalent Cu(1) and nine equivalent Al(1) atoms. Cu(1) is bonded to six equivalent Yb(1) and six equivalent Al(1) atoms to form CuYb6Al6 cuboctahedra that share corners with six equivalent Cu(1)Yb6Al6 cuboctahedra, corners with twelve equivalent Al(1)Yb6Al4Cu2 cuboctahedra, edges with six equivalent Cu(1)Yb6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Yb6Al4Cu2 cuboctahedra. Al(1) is bonded to six equivalent Yb(1), two equivalent Cu(1), and four equivalent Al(1) atoms to form AlYb6Al4Cu2 cuboctahedra that share corners with four equivalent Cu(1)Yb6Al6 cuboctahedra, corners with fourteen equivalent Al(1)Yb6Al4Cu2 cuboctahedra, edges with six equivalent Al(1)Yb6Al4Cu2 cuboctahedra, faces with six equivalent Cu(1)Yb6Al6 cuboctahedra, and faces with twelve equivalent Al(1)Yb6Al4Cu2 cuboctahedra. is represented by the CIF file [CIF]
data_Yb2Al3Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.439
_cell_length_b   5.439
_cell_length_c   5.439
_cell_angle_alpha   60.509
_cell_angle_beta   60.509
_cell_angle_gamma   60.509
_symmetry_Int_Tables_number   1
_cell_volume   115.097
_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
  Yb  Yb0  1  0.625  0.625  0.625  1.0
  Yb  Yb1  1  0.375  0.375  0.375  1.0
  Al  Al2  1  0.000  0.500  0.000  1.0
  Al  Al3  1  0.500  0.000  0.000  1.0
  Al  Al4  1  0.000  0.000  0.500  1.0
  Cu  Cu5  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Yb2CuAl3 crystallizes in the trigonal R-3m space group. Yb(1) is bonded in a 12-coordinate geometry to three equivalent Cu(1) and nine equivalent Al(1) atoms. Cu(1) is bonded to six equivalent Yb(1) and six equivalent Al(1) atoms to form CuYb6Al6 cuboctahedra that share corners with six equivalent Cu(1)Yb6Al6 cuboctahedra, corners with twelve equivalent Al(1)Yb6Al4Cu2 cuboctahedra, edges with six equivalent Cu(1)Yb6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Yb6Al4Cu2 cuboctahedra. Al(1) is bonded to six equivalent Yb(1), two equivalent Cu(1), and four equivalent Al(1) atoms to form AlYb6Al4Cu2 cuboctahedra that share corners with four equivalent Cu(1)Yb6Al6 cuboctahedra, corners with fourteen equivalent Al(1)Yb6Al4Cu2 cuboctahedra, edges with six equivalent Al(1)Yb6Al4Cu2 cuboctahedra, faces with six equivalent Cu(1)Yb6Al6 cuboctahedra, and faces with twelve equivalent Al(1)Yb6Al4Cu2 cuboctahedra. is represented by the CIF file [CIF]
data_Yb2Al3Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.439
_cell_length_b   5.439
_cell_length_c   5.439
_cell_angle_alpha   60.509
_cell_angle_beta   60.509
_cell_angle_gamma   60.509
_symmetry_Int_Tables_number   1
_cell_volume   115.097
_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
  Yb  Yb0  1  0.625  0.625  0.625  1.0
  Yb  Yb1  1  0.375  0.375  0.375  1.0
  Al  Al2  1  0.000  0.500  0.000  1.0
  Al  Al3  1  0.500  0.000  0.000  1.0
  Al  Al4  1  0.000  0.000  0.500  1.0
  Cu  Cu5  1  0.000  0.000  0.000  1.0
[/CIF]
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