The crystal structure described by Dy2Al17 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a 18-coordinate geometry to six equivalent Al(3) and twelve equivalent Al(4) atoms. In the second Dy site, Dy(2) is bonded in a 20-coordinate geometry to two equivalent Al(1), six equivalent Al(2), six equivalent Al(3), and six equivalent Al(4) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a 14-coordinate geometry to one Dy(2), one Al(1), three equivalent Al(2), three equivalent Al(4), and six equivalent Al(3) atoms. In the second Al site, Al(2) is bonded to two equivalent Dy(2), two equivalent Al(1), four equivalent Al(3), and four equivalent Al(4) atoms to form AlDy2Al10 cuboctahedra that share corners with four equivalent Al(2)Dy2Al10 cuboctahedra, corners with ten equivalent Al(4)Dy3Al9 cuboctahedra, edges with six equivalent Al(4)Dy3Al9 cuboctahedra, faces with four equivalent Al(4)Dy3Al9 cuboctahedra, and faces with six equivalent Al(2)Dy2Al10 cuboctahedra. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Dy(1), one Dy(2), two equivalent Al(1), two equivalent Al(2), two equivalent Al(3), and four equivalent Al(4) atoms. In the fourth Al site, Al(4) is bonded to one Dy(2), two equivalent Dy(1), one Al(1), two equivalent Al(2), two equivalent Al(4), and four equivalent Al(3) atoms to form distorted AlDy3Al9 cuboctahedra that share corners with five equivalent Al(2)Dy2Al10 cuboctahedra, corners with ten equivalent Al(4)Dy3Al9 cuboctahedra, edges with three equivalent Al(2)Dy2Al10 cuboctahedra, edges with five equivalent Al(4)Dy3Al9 cuboctahedra, faces with two equivalent Al(2)Dy2Al10 cuboctahedra, and faces with eight equivalent Al(4)Dy3Al9 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Dy2Al17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.473
_cell_length_b   9.473
_cell_length_c   8.876
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   689.787
_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
  Dy  Dy0  1  0.000  0.000  0.250  1.0
  Dy  Dy1  1  0.000  0.000  0.750  1.0
  Dy  Dy2  1  0.333  0.667  0.750  1.0
  Dy  Dy3  1  0.667  0.333  0.250  1.0
  Al  Al4  1  0.333  0.667  0.399  1.0
  Al  Al5  1  0.667  0.333  0.601  1.0
  Al  Al6  1  0.667  0.333  0.899  1.0
  Al  Al7  1  0.333  0.667  0.101  1.0
  Al  Al8  1  0.500  0.500  0.500  1.0
  Al  Al9  1  0.500  0.000  0.500  1.0
  Al  Al10  1  0.000  0.500  0.500  1.0
  Al  Al11  1  0.500  0.500  0.000  1.0
  Al  Al12  1  0.500  0.000  0.000  1.0
  Al  Al13  1  0.000  0.500  0.000  1.0
  Al  Al14  1  0.327  0.363  0.250  1.0
  Al  Al15  1  0.637  0.964  0.250  1.0
  Al  Al16  1  0.036  0.673  0.250  1.0
  Al  Al17  1  0.637  0.673  0.250  1.0
  Al  Al18  1  0.036  0.363  0.250  1.0
  Al  Al19  1  0.327  0.964  0.250  1.0
  Al  Al20  1  0.673  0.637  0.750  1.0
  Al  Al21  1  0.363  0.036  0.750  1.0
  Al  Al22  1  0.964  0.327  0.750  1.0
  Al  Al23  1  0.363  0.327  0.750  1.0
  Al  Al24  1  0.964  0.637  0.750  1.0
  Al  Al25  1  0.673  0.036  0.750  1.0
  Al  Al26  1  0.163  0.837  0.526  1.0
  Al  Al27  1  0.163  0.326  0.526  1.0
  Al  Al28  1  0.674  0.837  0.526  1.0
  Al  Al29  1  0.837  0.163  0.474  1.0
  Al  Al30  1  0.837  0.674  0.474  1.0
  Al  Al31  1  0.326  0.163  0.474  1.0
  Al  Al32  1  0.837  0.163  0.026  1.0
  Al  Al33  1  0.837  0.674  0.026  1.0
  Al  Al34  1  0.326  0.163  0.026  1.0
  Al  Al35  1  0.163  0.837  0.974  1.0
  Al  Al36  1  0.163  0.326  0.974  1.0
  Al  Al37  1  0.674  0.837  0.974  1.0
[/CIF]
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The crystal structure described by Dy2Al17 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a 18-coordinate geometry to six equivalent Al(3) and twelve equivalent Al(4) atoms. In the second Dy site, Dy(2) is bonded in a 20-coordinate geometry to two equivalent Al(1), six equivalent Al(2), six equivalent Al(3), and six equivalent Al(4) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a 14-coordinate geometry to one Dy(2), one Al(1), three equivalent Al(2), three equivalent Al(4), and six equivalent Al(3) atoms. In the second Al site, Al(2) is bonded to two equivalent Dy(2), two equivalent Al(1), four equivalent Al(3), and four equivalent Al(4) atoms to form AlDy2Al10 cuboctahedra that share corners with four equivalent Al(2)Dy2Al10 cuboctahedra, corners with ten equivalent Al(4)Dy3Al9 cuboctahedra, edges with six equivalent Al(4)Dy3Al9 cuboctahedra, faces with four equivalent Al(4)Dy3Al9 cuboctahedra, and faces with six equivalent Al(2)Dy2Al10 cuboctahedra. In the third Al site, Al(3) is bonded in a 10-coordinate geometry to one Dy(1), one Dy(2), two equivalent Al(1), two equivalent Al(2), two equivalent Al(3), and four equivalent Al(4) atoms. In the fourth Al site, Al(4) is bonded to one Dy(2), two equivalent Dy(1), one Al(1), two equivalent Al(2), two equivalent Al(4), and four equivalent Al(3) atoms to form distorted AlDy3Al9 cuboctahedra that share corners with five equivalent Al(2)Dy2Al10 cuboctahedra, corners with ten equivalent Al(4)Dy3Al9 cuboctahedra, edges with three equivalent Al(2)Dy2Al10 cuboctahedra, edges with five equivalent Al(4)Dy3Al9 cuboctahedra, faces with two equivalent Al(2)Dy2Al10 cuboctahedra, and faces with eight equivalent Al(4)Dy3Al9 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Dy2Al17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.473
_cell_length_b   9.473
_cell_length_c   8.876
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   689.787
_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
  Dy  Dy0  1  0.000  0.000  0.250  1.0
  Dy  Dy1  1  0.000  0.000  0.750  1.0
  Dy  Dy2  1  0.333  0.667  0.750  1.0
  Dy  Dy3  1  0.667  0.333  0.250  1.0
  Al  Al4  1  0.333  0.667  0.399  1.0
  Al  Al5  1  0.667  0.333  0.601  1.0
  Al  Al6  1  0.667  0.333  0.899  1.0
  Al  Al7  1  0.333  0.667  0.101  1.0
  Al  Al8  1  0.500  0.500  0.500  1.0
  Al  Al9  1  0.500  0.000  0.500  1.0
  Al  Al10  1  0.000  0.500  0.500  1.0
  Al  Al11  1  0.500  0.500  0.000  1.0
  Al  Al12  1  0.500  0.000  0.000  1.0
  Al  Al13  1  0.000  0.500  0.000  1.0
  Al  Al14  1  0.327  0.363  0.250  1.0
  Al  Al15  1  0.637  0.964  0.250  1.0
  Al  Al16  1  0.036  0.673  0.250  1.0
  Al  Al17  1  0.637  0.673  0.250  1.0
  Al  Al18  1  0.036  0.363  0.250  1.0
  Al  Al19  1  0.327  0.964  0.250  1.0
  Al  Al20  1  0.673  0.637  0.750  1.0
  Al  Al21  1  0.363  0.036  0.750  1.0
  Al  Al22  1  0.964  0.327  0.750  1.0
  Al  Al23  1  0.363  0.327  0.750  1.0
  Al  Al24  1  0.964  0.637  0.750  1.0
  Al  Al25  1  0.673  0.036  0.750  1.0
  Al  Al26  1  0.163  0.837  0.526  1.0
  Al  Al27  1  0.163  0.326  0.526  1.0
  Al  Al28  1  0.674  0.837  0.526  1.0
  Al  Al29  1  0.837  0.163  0.474  1.0
  Al  Al30  1  0.837  0.674  0.474  1.0
  Al  Al31  1  0.326  0.163  0.474  1.0
  Al  Al32  1  0.837  0.163  0.026  1.0
  Al  Al33  1  0.837  0.674  0.026  1.0
  Al  Al34  1  0.326  0.163  0.026  1.0
  Al  Al35  1  0.163  0.837  0.974  1.0
  Al  Al36  1  0.163  0.326  0.974  1.0
  Al  Al37  1  0.674  0.837  0.974  1.0
[/CIF]
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