The structure described by Y3Cu2Al7 crystallizes in the trigonal R-3m space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 18-coordinate geometry to six equivalent Cu(1) and twelve equivalent Al(1) atoms. In the second Y site, Y(2) is bonded in a 12-coordinate geometry to three equivalent Al(2) and nine equivalent Al(1) atoms. Cu(1) is bonded in a 9-coordinate geometry to three equivalent Y(1) and six equivalent Al(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 2-coordinate geometry to two equivalent Y(1), three equivalent Y(2), two equivalent Cu(1), and one Al(2) atom. In the second Al site, Al(2) is bonded to six equivalent Y(2) and six equivalent Al(1) atoms to form edge-sharing AlY6Al6 cuboctahedra. is represented by the CIF card [CIF]
data_Y3Al7Cu2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.013
_cell_length_b   9.013
_cell_length_c   9.013
_cell_angle_alpha   35.345
_cell_angle_beta   35.345
_cell_angle_gamma   35.345
_symmetry_Int_Tables_number   1
_cell_volume   218.921
_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
  Y  Y0  1  0.000  0.000  0.000  1.0
  Y  Y1  1  0.858  0.858  0.858  1.0
  Y  Y2  1  0.142  0.142  0.142  1.0
  Al  Al3  1  0.419  0.419  0.928  1.0
  Al  Al4  1  0.928  0.419  0.419  1.0
  Al  Al5  1  0.419  0.928  0.419  1.0
  Al  Al6  1  0.500  0.500  0.500  1.0
  Al  Al7  1  0.581  0.072  0.581  1.0
  Al  Al8  1  0.072  0.581  0.581  1.0
  Al  Al9  1  0.581  0.581  0.072  1.0
  Cu  Cu10  1  0.665  0.665  0.665  1.0
  Cu  Cu11  1  0.335  0.335  0.335  1.0
[/CIF]
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The structure described by Y3Cu2Al7 crystallizes in the trigonal R-3m space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 18-coordinate geometry to six equivalent Cu(1) and twelve equivalent Al(1) atoms. In the second Y site, Y(2) is bonded in a 12-coordinate geometry to three equivalent Al(2) and nine equivalent Al(1) atoms. Cu(1) is bonded in a 9-coordinate geometry to three equivalent Y(1) and six equivalent Al(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 2-coordinate geometry to two equivalent Y(1), three equivalent Y(2), two equivalent Cu(1), and one Al(2) atom. In the second Al site, Al(2) is bonded to six equivalent Y(2) and six equivalent Al(1) atoms to form edge-sharing AlY6Al6 cuboctahedra. is represented by the CIF card [CIF]
data_Y3Al7Cu2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.013
_cell_length_b   9.013
_cell_length_c   9.013
_cell_angle_alpha   35.345
_cell_angle_beta   35.345
_cell_angle_gamma   35.345
_symmetry_Int_Tables_number   1
_cell_volume   218.921
_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
  Y  Y0  1  0.000  0.000  0.000  1.0
  Y  Y1  1  0.858  0.858  0.858  1.0
  Y  Y2  1  0.142  0.142  0.142  1.0
  Al  Al3  1  0.419  0.419  0.928  1.0
  Al  Al4  1  0.928  0.419  0.419  1.0
  Al  Al5  1  0.419  0.928  0.419  1.0
  Al  Al6  1  0.500  0.500  0.500  1.0
  Al  Al7  1  0.581  0.072  0.581  1.0
  Al  Al8  1  0.072  0.581  0.581  1.0
  Al  Al9  1  0.581  0.581  0.072  1.0
  Cu  Cu10  1  0.665  0.665  0.665  1.0
  Cu  Cu11  1  0.335  0.335  0.335  1.0
[/CIF]
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