The structure described by YbCuAl2 crystallizes in the trigonal R-3m space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 18-coordinate geometry to six equivalent Cu(1) and twelve equivalent Al(1) atoms. In the second Yb site, Yb(2) is bonded in a 12-coordinate geometry to three equivalent Cu(2) and nine equivalent Al(1) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 9-coordinate geometry to three equivalent Yb(1) and six equivalent Al(1) atoms. In the second Cu site, Cu(2) is bonded to six equivalent Yb(2) and six equivalent Al(1) atoms to form CuYb6Al6 cuboctahedra that share corners with twelve equivalent Al(1)Yb5Al4Cu3 cuboctahedra, edges with six equivalent Cu(2)Yb6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Yb5Al4Cu3 cuboctahedra. Al(1) is bonded to two equivalent Yb(1), three equivalent Yb(2), one Cu(2), two equivalent Cu(1), and four equivalent Al(1) atoms to form distorted AlYb5Al4Cu3 cuboctahedra that share corners with two equivalent Cu(2)Yb6Al6 cuboctahedra, corners with fifteen equivalent Al(1)Yb5Al4Cu3 cuboctahedra, edges with eight equivalent Al(1)Yb5Al4Cu3 cuboctahedra, faces with three equivalent Cu(2)Yb6Al6 cuboctahedra, and faces with eleven equivalent Al(1)Yb5Al4Cu3 cuboctahedra. is represented by the CIF card [CIF]
data_YbAl2Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.020
_cell_length_b   9.020
_cell_length_c   9.020
_cell_angle_alpha   34.930
_cell_angle_beta   34.930
_cell_angle_gamma   34.930
_symmetry_Int_Tables_number   1
_cell_volume   214.781
_cell_formula_units_Z   3
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  0.000  0.000  0.000  1.0
  Yb  Yb1  1  0.145  0.145  0.145  1.0
  Yb  Yb2  1  0.855  0.855  0.855  1.0
  Al  Al3  1  0.079  0.579  0.579  1.0
  Al  Al4  1  0.579  0.079  0.579  1.0
  Al  Al5  1  0.579  0.579  0.079  1.0
  Al  Al6  1  0.421  0.421  0.921  1.0
  Al  Al7  1  0.421  0.921  0.421  1.0
  Al  Al8  1  0.921  0.421  0.421  1.0
  Cu  Cu9  1  0.335  0.335  0.335  1.0
  Cu  Cu10  1  0.500  0.500  0.500  1.0
  Cu  Cu11  1  0.665  0.665  0.665  1.0
[/CIF]
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The structure described by YbCuAl2 crystallizes in the trigonal R-3m space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 18-coordinate geometry to six equivalent Cu(1) and twelve equivalent Al(1) atoms. In the second Yb site, Yb(2) is bonded in a 12-coordinate geometry to three equivalent Cu(2) and nine equivalent Al(1) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 9-coordinate geometry to three equivalent Yb(1) and six equivalent Al(1) atoms. In the second Cu site, Cu(2) is bonded to six equivalent Yb(2) and six equivalent Al(1) atoms to form CuYb6Al6 cuboctahedra that share corners with twelve equivalent Al(1)Yb5Al4Cu3 cuboctahedra, edges with six equivalent Cu(2)Yb6Al6 cuboctahedra, and faces with eighteen equivalent Al(1)Yb5Al4Cu3 cuboctahedra. Al(1) is bonded to two equivalent Yb(1), three equivalent Yb(2), one Cu(2), two equivalent Cu(1), and four equivalent Al(1) atoms to form distorted AlYb5Al4Cu3 cuboctahedra that share corners with two equivalent Cu(2)Yb6Al6 cuboctahedra, corners with fifteen equivalent Al(1)Yb5Al4Cu3 cuboctahedra, edges with eight equivalent Al(1)Yb5Al4Cu3 cuboctahedra, faces with three equivalent Cu(2)Yb6Al6 cuboctahedra, and faces with eleven equivalent Al(1)Yb5Al4Cu3 cuboctahedra. is represented by the CIF card [CIF]
data_YbAl2Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.020
_cell_length_b   9.020
_cell_length_c   9.020
_cell_angle_alpha   34.930
_cell_angle_beta   34.930
_cell_angle_gamma   34.930
_symmetry_Int_Tables_number   1
_cell_volume   214.781
_cell_formula_units_Z   3
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  0.000  0.000  0.000  1.0
  Yb  Yb1  1  0.145  0.145  0.145  1.0
  Yb  Yb2  1  0.855  0.855  0.855  1.0
  Al  Al3  1  0.079  0.579  0.579  1.0
  Al  Al4  1  0.579  0.079  0.579  1.0
  Al  Al5  1  0.579  0.579  0.079  1.0
  Al  Al6  1  0.421  0.421  0.921  1.0
  Al  Al7  1  0.421  0.921  0.421  1.0
  Al  Al8  1  0.921  0.421  0.421  1.0
  Cu  Cu9  1  0.335  0.335  0.335  1.0
  Cu  Cu10  1  0.500  0.500  0.500  1.0
  Cu  Cu11  1  0.665  0.665  0.665  1.0
[/CIF]
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