The compound described by ErYAl6 crystallizes in the trigonal R3m space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded to three equivalent Al(2), three equivalent Al(3), and six equivalent Al(5) atoms to form ErAl12 cuboctahedra that share corners with six equivalent Er(1)Al12 cuboctahedra,  a faceface with one Y(1)Al12 cuboctahedra,  a faceface with one Y(2)Al12 cuboctahedra, faces with three equivalent Er(3)Al12 cuboctahedra, and faces with three equivalent Y(3)Al12 cuboctahedra. In the second Er site, Er(2) is bonded to three equivalent Al(1), three equivalent Al(4), and six equivalent Al(6) atoms to form ErAl12 cuboctahedra that share corners with six equivalent Er(2)Al12 cuboctahedra,  a faceface with one Er(3)Al12 cuboctahedra,  a faceface with one Y(3)Al12 cuboctahedra, faces with three equivalent Y(1)Al12 cuboctahedra, and faces with three equivalent Y(2)Al12 cuboctahedra. In the third Er site, Er(3) is bonded to three equivalent Al(1), three equivalent Al(5), and six equivalent Al(3) atoms to form distorted ErAl12 cuboctahedra that share corners with three equivalent Y(3)Al12 cuboctahedra, corners with six equivalent Er(3)Al12 cuboctahedra,  a faceface with one Er(2)Al12 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, and faces with three equivalent Y(2)Al12 cuboctahedra. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded to three equivalent Al(2), three equivalent Al(6), and six equivalent Al(4) atoms to form distorted YAl12 cuboctahedra that share corners with three equivalent Y(2)Al12 cuboctahedra, corners with six equivalent Y(1)Al12 cuboctahedra,  a faceface with one Er(1)Al12 cuboctahedra, faces with three equivalent Er(2)Al12 cuboctahedra, and faces with three equivalent Y(3)Al12 cuboctahedra. In the second Y site, Y(2) is bonded to three equivalent Al(3), three equivalent Al(6), and six equivalent Al(1) atoms to form distorted YAl12 cuboctahedra that share corners with three equivalent Y(1)Al12 cuboctahedra, corners with six equivalent Y(2)Al12 cuboctahedra,  a faceface with one Er(1)Al12 cuboctahedra, faces with three equivalent Er(2)Al12 cuboctahedra, and faces with three equivalent Er(3)Al12 cuboctahedra. In the third Y site, Y(3) is bonded to three equivalent Al(4), three equivalent Al(5), and six equivalent Al(2) atoms to form distorted YAl12 cuboctahedra that share corners with three equivalent Er(3)Al12 cuboctahedra, corners with six equivalent Y(3)Al12 cuboctahedra,  a faceface with one Er(2)Al12 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, and faces with three equivalent Y(1)Al12 cuboctahedra. There are six inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Er(2), one Er(3), two equivalent Y(2), two equivalent Al(1), two equivalent Al(3), and two equivalent Al(6) atoms. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to one Er(1), one Y(1), two equivalent Y(3), two equivalent Al(2), two equivalent Al(4), and two equivalent Al(5) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Er(1), two equivalent Er(3), one Y(2), two equivalent Al(1), two equivalent Al(3), and two equivalent Al(5) atoms. In the fourth Al site, Al(4) is bonded in a 10-coordinate geometry to one Er(2), one Y(3), two equivalent Y(1), two equivalent Al(2), two equivalent Al(4), and two equivalent Al(6) atoms. In the fifth Al site, Al(5) is bonded in a 8-coordinate geometry to one Er(3), two equivalent Er(1), one Y(3), two equivalent Al(2), and two equivalent Al(3) atoms. In the sixth Al site, Al(6) is bonded in a 8-coordinate geometry to two equivalent Er(2), one Y(1), one Y(2), two equivalent Al(1), and two equivalent Al(4) atoms. is represented by the CIF card [CIF]
data_YErAl6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.416
_cell_length_b   14.416
_cell_length_c   14.416
_cell_angle_alpha   25.015
_cell_angle_beta   25.015
_cell_angle_gamma   25.015
_symmetry_Int_Tables_number   1
_cell_volume   471.334
_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
  Y  Y0  1  0.109  0.109  0.109  1.0
  Y  Y1  1  0.891  0.891  0.891  1.0
  Y  Y2  1  0.391  0.391  0.391  1.0
  Er  Er3  1  1.000  1.000  1.000  1.0
  Er  Er4  1  0.500  0.500  0.500  1.0
  Er  Er5  1  0.609  0.609  0.609  1.0
  Al  Al6  1  0.929  0.369  0.369  1.0
  Al  Al7  1  0.430  0.868  0.868  1.0
  Al  Al8  1  0.369  0.369  0.929  1.0
  Al  Al9  1  0.868  0.868  0.430  1.0
  Al  Al10  1  0.369  0.929  0.369  1.0
  Al  Al11  1  0.868  0.430  0.868  1.0
  Al  Al12  1  0.570  0.132  0.132  1.0
  Al  Al13  1  0.070  0.632  0.632  1.0
  Al  Al14  1  0.132  0.132  0.570  1.0
  Al  Al15  1  0.632  0.632  0.070  1.0
  Al  Al16  1  0.132  0.570  0.132  1.0
  Al  Al17  1  0.632  0.070  0.632  1.0
  Al  Al18  1  0.501  0.501  0.998  1.0
  Al  Al19  1  0.000  0.000  0.500  1.0
  Al  Al20  1  0.501  0.998  0.501  1.0
  Al  Al21  1  0.000  0.500  0.000  1.0
  Al  Al22  1  0.998  0.501  0.501  1.0
  Al  Al23  1  0.500  0.000  0.000  1.0
[/CIF]
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The compound described by ErYAl6 crystallizes in the trigonal R3m space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded to three equivalent Al(2), three equivalent Al(3), and six equivalent Al(5) atoms to form ErAl12 cuboctahedra that share corners with six equivalent Er(1)Al12 cuboctahedra,  a faceface with one Y(1)Al12 cuboctahedra,  a faceface with one Y(2)Al12 cuboctahedra, faces with three equivalent Er(3)Al12 cuboctahedra, and faces with three equivalent Y(3)Al12 cuboctahedra. In the second Er site, Er(2) is bonded to three equivalent Al(1), three equivalent Al(4), and six equivalent Al(6) atoms to form ErAl12 cuboctahedra that share corners with six equivalent Er(2)Al12 cuboctahedra,  a faceface with one Er(3)Al12 cuboctahedra,  a faceface with one Y(3)Al12 cuboctahedra, faces with three equivalent Y(1)Al12 cuboctahedra, and faces with three equivalent Y(2)Al12 cuboctahedra. In the third Er site, Er(3) is bonded to three equivalent Al(1), three equivalent Al(5), and six equivalent Al(3) atoms to form distorted ErAl12 cuboctahedra that share corners with three equivalent Y(3)Al12 cuboctahedra, corners with six equivalent Er(3)Al12 cuboctahedra,  a faceface with one Er(2)Al12 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, and faces with three equivalent Y(2)Al12 cuboctahedra. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded to three equivalent Al(2), three equivalent Al(6), and six equivalent Al(4) atoms to form distorted YAl12 cuboctahedra that share corners with three equivalent Y(2)Al12 cuboctahedra, corners with six equivalent Y(1)Al12 cuboctahedra,  a faceface with one Er(1)Al12 cuboctahedra, faces with three equivalent Er(2)Al12 cuboctahedra, and faces with three equivalent Y(3)Al12 cuboctahedra. In the second Y site, Y(2) is bonded to three equivalent Al(3), three equivalent Al(6), and six equivalent Al(1) atoms to form distorted YAl12 cuboctahedra that share corners with three equivalent Y(1)Al12 cuboctahedra, corners with six equivalent Y(2)Al12 cuboctahedra,  a faceface with one Er(1)Al12 cuboctahedra, faces with three equivalent Er(2)Al12 cuboctahedra, and faces with three equivalent Er(3)Al12 cuboctahedra. In the third Y site, Y(3) is bonded to three equivalent Al(4), three equivalent Al(5), and six equivalent Al(2) atoms to form distorted YAl12 cuboctahedra that share corners with three equivalent Er(3)Al12 cuboctahedra, corners with six equivalent Y(3)Al12 cuboctahedra,  a faceface with one Er(2)Al12 cuboctahedra, faces with three equivalent Er(1)Al12 cuboctahedra, and faces with three equivalent Y(1)Al12 cuboctahedra. There are six inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Er(2), one Er(3), two equivalent Y(2), two equivalent Al(1), two equivalent Al(3), and two equivalent Al(6) atoms. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to one Er(1), one Y(1), two equivalent Y(3), two equivalent Al(2), two equivalent Al(4), and two equivalent Al(5) atoms. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Er(1), two equivalent Er(3), one Y(2), two equivalent Al(1), two equivalent Al(3), and two equivalent Al(5) atoms. In the fourth Al site, Al(4) is bonded in a 10-coordinate geometry to one Er(2), one Y(3), two equivalent Y(1), two equivalent Al(2), two equivalent Al(4), and two equivalent Al(6) atoms. In the fifth Al site, Al(5) is bonded in a 8-coordinate geometry to one Er(3), two equivalent Er(1), one Y(3), two equivalent Al(2), and two equivalent Al(3) atoms. In the sixth Al site, Al(6) is bonded in a 8-coordinate geometry to two equivalent Er(2), one Y(1), one Y(2), two equivalent Al(1), and two equivalent Al(4) atoms. is represented by the CIF card [CIF]
data_YErAl6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.416
_cell_length_b   14.416
_cell_length_c   14.416
_cell_angle_alpha   25.015
_cell_angle_beta   25.015
_cell_angle_gamma   25.015
_symmetry_Int_Tables_number   1
_cell_volume   471.334
_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
  Y  Y0  1  0.109  0.109  0.109  1.0
  Y  Y1  1  0.891  0.891  0.891  1.0
  Y  Y2  1  0.391  0.391  0.391  1.0
  Er  Er3  1  1.000  1.000  1.000  1.0
  Er  Er4  1  0.500  0.500  0.500  1.0
  Er  Er5  1  0.609  0.609  0.609  1.0
  Al  Al6  1  0.929  0.369  0.369  1.0
  Al  Al7  1  0.430  0.868  0.868  1.0
  Al  Al8  1  0.369  0.369  0.929  1.0
  Al  Al9  1  0.868  0.868  0.430  1.0
  Al  Al10  1  0.369  0.929  0.369  1.0
  Al  Al11  1  0.868  0.430  0.868  1.0
  Al  Al12  1  0.570  0.132  0.132  1.0
  Al  Al13  1  0.070  0.632  0.632  1.0
  Al  Al14  1  0.132  0.132  0.570  1.0
  Al  Al15  1  0.632  0.632  0.070  1.0
  Al  Al16  1  0.132  0.570  0.132  1.0
  Al  Al17  1  0.632  0.070  0.632  1.0
  Al  Al18  1  0.501  0.501  0.998  1.0
  Al  Al19  1  0.000  0.000  0.500  1.0
  Al  Al20  1  0.501  0.998  0.501  1.0
  Al  Al21  1  0.000  0.500  0.000  1.0
  Al  Al22  1  0.998  0.501  0.501  1.0
  Al  Al23  1  0.500  0.000  0.000  1.0
[/CIF]
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