The compound described by Dy2Nb2Fe15 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 Fe(2) and twelve equivalent Fe(3) atoms. In the second Dy site, Dy(2) is bonded in a 20-coordinate geometry to two equivalent Nb(1), six equivalent Fe(1), six equivalent Fe(2), and six equivalent Fe(3) atoms. Nb(1) is bonded in a 14-coordinate geometry to one Dy(2), one Nb(1), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Dy(2), two equivalent Nb(1), four equivalent Fe(2), and four equivalent Fe(3) atoms to form distorted FeDy2Nb2Fe8 cuboctahedra that share corners with four equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, corners with eight equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, corners with ten equivalent Fe(3)Dy3NbFe8 cuboctahedra, edges with four equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, edges with six equivalent Fe(3)Dy3NbFe8 cuboctahedra, faces with four equivalent Fe(3)Dy3NbFe8 cuboctahedra, faces with six equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, and faces with eight equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra. In the second Fe site, Fe(2) is bonded to one Dy(1), one Dy(2), two equivalent Nb(1), two equivalent Fe(1), two equivalent Fe(2), and four equivalent Fe(3) atoms to form distorted FeDy2Nb2Fe8 cuboctahedra that share corners with four equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, corners with eight equivalent Fe(3)Dy3NbFe8 cuboctahedra, corners with twelve equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra,  an edgeedge with one Fe(2)Dy2Nb2Fe8 cuboctahedra, edges with two equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, edges with two equivalent Fe(3)Dy3NbFe8 cuboctahedra, faces with four equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, faces with seven equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, and faces with ten equivalent Fe(3)Dy3NbFe8 cuboctahedra. In the third Fe site, Fe(3) is bonded to one Dy(2), two equivalent Dy(1), one Nb(1), two equivalent Fe(1), two equivalent Fe(3), and four equivalent Fe(2) atoms to form distorted FeDy3NbFe8 cuboctahedra that share corners with five equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, corners with eight equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, corners with ten equivalent Fe(3)Dy3NbFe8 cuboctahedra, edges with two equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, edges with three equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, edges with five equivalent Fe(3)Dy3NbFe8 cuboctahedra, faces with two equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, faces with eight equivalent Fe(3)Dy3NbFe8 cuboctahedra, and faces with ten equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Dy2Nb2Fe15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.475
_cell_length_b   8.492
_cell_length_c   8.492
_cell_angle_alpha   120.002
_cell_angle_beta   89.999
_cell_angle_gamma   90.002
_symmetry_Int_Tables_number   1
_cell_volume   529.310
_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  0.750  1.000  0.000  1.0
  Dy  Dy1  1  0.250  0.000  1.000  1.0
  Dy  Dy2  1  0.250  0.667  0.333  1.0
  Dy  Dy3  1  0.750  0.333  0.667  1.0
  Nb  Nb4  1  0.599  0.667  0.333  1.0
  Nb  Nb5  1  0.401  0.333  0.667  1.0
  Nb  Nb6  1  0.099  0.333  0.667  1.0
  Nb  Nb7  1  0.901  0.667  0.333  1.0
  Fe  Fe8  1  0.500  0.500  1.000  1.0
  Fe  Fe9  1  0.500  0.500  0.500  1.0
  Fe  Fe10  1  0.500  0.000  0.500  1.0
  Fe  Fe11  1  0.000  0.500  0.000  1.0
  Fe  Fe12  1  0.000  0.500  0.500  1.0
  Fe  Fe13  1  0.000  0.000  0.500  1.0
  Fe  Fe14  1  0.750  0.670  0.028  1.0
  Fe  Fe15  1  0.750  0.358  0.330  1.0
  Fe  Fe16  1  0.750  0.972  0.642  1.0
  Fe  Fe17  1  0.750  0.358  0.028  1.0
  Fe  Fe18  1  0.750  0.972  0.330  1.0
  Fe  Fe19  1  0.750  0.670  0.642  1.0
  Fe  Fe20  1  0.250  0.330  0.972  1.0
  Fe  Fe21  1  0.250  0.642  0.670  1.0
  Fe  Fe22  1  0.250  0.028  0.358  1.0
  Fe  Fe23  1  0.250  0.642  0.972  1.0
  Fe  Fe24  1  0.250  0.028  0.670  1.0
  Fe  Fe25  1  0.250  0.330  0.358  1.0
  Fe  Fe26  1  0.488  0.837  0.674  1.0
  Fe  Fe27  1  0.488  0.837  0.163  1.0
  Fe  Fe28  1  0.488  0.326  0.163  1.0
  Fe  Fe29  1  0.512  0.163  0.326  1.0
  Fe  Fe30  1  0.512  0.163  0.837  1.0
  Fe  Fe31  1  0.512  0.674  0.837  1.0
  Fe  Fe32  1  0.988  0.163  0.326  1.0
  Fe  Fe33  1  0.988  0.163  0.837  1.0
  Fe  Fe34  1  0.988  0.674  0.837  1.0
  Fe  Fe35  1  0.012  0.837  0.674  1.0
  Fe  Fe36  1  0.012  0.837  0.163  1.0
  Fe  Fe37  1  0.012  0.326  0.163  1.0
[/CIF]
.
The compound described by Dy2Nb2Fe15 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 Fe(2) and twelve equivalent Fe(3) atoms. In the second Dy site, Dy(2) is bonded in a 20-coordinate geometry to two equivalent Nb(1), six equivalent Fe(1), six equivalent Fe(2), and six equivalent Fe(3) atoms. Nb(1) is bonded in a 14-coordinate geometry to one Dy(2), one Nb(1), three equivalent Fe(1), three equivalent Fe(3), and six equivalent Fe(2) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Dy(2), two equivalent Nb(1), four equivalent Fe(2), and four equivalent Fe(3) atoms to form distorted FeDy2Nb2Fe8 cuboctahedra that share corners with four equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, corners with eight equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, corners with ten equivalent Fe(3)Dy3NbFe8 cuboctahedra, edges with four equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, edges with six equivalent Fe(3)Dy3NbFe8 cuboctahedra, faces with four equivalent Fe(3)Dy3NbFe8 cuboctahedra, faces with six equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, and faces with eight equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra. In the second Fe site, Fe(2) is bonded to one Dy(1), one Dy(2), two equivalent Nb(1), two equivalent Fe(1), two equivalent Fe(2), and four equivalent Fe(3) atoms to form distorted FeDy2Nb2Fe8 cuboctahedra that share corners with four equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, corners with eight equivalent Fe(3)Dy3NbFe8 cuboctahedra, corners with twelve equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra,  an edgeedge with one Fe(2)Dy2Nb2Fe8 cuboctahedra, edges with two equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, edges with two equivalent Fe(3)Dy3NbFe8 cuboctahedra, faces with four equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, faces with seven equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, and faces with ten equivalent Fe(3)Dy3NbFe8 cuboctahedra. In the third Fe site, Fe(3) is bonded to one Dy(2), two equivalent Dy(1), one Nb(1), two equivalent Fe(1), two equivalent Fe(3), and four equivalent Fe(2) atoms to form distorted FeDy3NbFe8 cuboctahedra that share corners with five equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, corners with eight equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, corners with ten equivalent Fe(3)Dy3NbFe8 cuboctahedra, edges with two equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra, edges with three equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, edges with five equivalent Fe(3)Dy3NbFe8 cuboctahedra, faces with two equivalent Fe(1)Dy2Nb2Fe8 cuboctahedra, faces with eight equivalent Fe(3)Dy3NbFe8 cuboctahedra, and faces with ten equivalent Fe(2)Dy2Nb2Fe8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Dy2Nb2Fe15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.475
_cell_length_b   8.492
_cell_length_c   8.492
_cell_angle_alpha   120.002
_cell_angle_beta   89.999
_cell_angle_gamma   90.002
_symmetry_Int_Tables_number   1
_cell_volume   529.310
_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  0.750  1.000  0.000  1.0
  Dy  Dy1  1  0.250  0.000  1.000  1.0
  Dy  Dy2  1  0.250  0.667  0.333  1.0
  Dy  Dy3  1  0.750  0.333  0.667  1.0
  Nb  Nb4  1  0.599  0.667  0.333  1.0
  Nb  Nb5  1  0.401  0.333  0.667  1.0
  Nb  Nb6  1  0.099  0.333  0.667  1.0
  Nb  Nb7  1  0.901  0.667  0.333  1.0
  Fe  Fe8  1  0.500  0.500  1.000  1.0
  Fe  Fe9  1  0.500  0.500  0.500  1.0
  Fe  Fe10  1  0.500  0.000  0.500  1.0
  Fe  Fe11  1  0.000  0.500  0.000  1.0
  Fe  Fe12  1  0.000  0.500  0.500  1.0
  Fe  Fe13  1  0.000  0.000  0.500  1.0
  Fe  Fe14  1  0.750  0.670  0.028  1.0
  Fe  Fe15  1  0.750  0.358  0.330  1.0
  Fe  Fe16  1  0.750  0.972  0.642  1.0
  Fe  Fe17  1  0.750  0.358  0.028  1.0
  Fe  Fe18  1  0.750  0.972  0.330  1.0
  Fe  Fe19  1  0.750  0.670  0.642  1.0
  Fe  Fe20  1  0.250  0.330  0.972  1.0
  Fe  Fe21  1  0.250  0.642  0.670  1.0
  Fe  Fe22  1  0.250  0.028  0.358  1.0
  Fe  Fe23  1  0.250  0.642  0.972  1.0
  Fe  Fe24  1  0.250  0.028  0.670  1.0
  Fe  Fe25  1  0.250  0.330  0.358  1.0
  Fe  Fe26  1  0.488  0.837  0.674  1.0
  Fe  Fe27  1  0.488  0.837  0.163  1.0
  Fe  Fe28  1  0.488  0.326  0.163  1.0
  Fe  Fe29  1  0.512  0.163  0.326  1.0
  Fe  Fe30  1  0.512  0.163  0.837  1.0
  Fe  Fe31  1  0.512  0.674  0.837  1.0
  Fe  Fe32  1  0.988  0.163  0.326  1.0
  Fe  Fe33  1  0.988  0.163  0.837  1.0
  Fe  Fe34  1  0.988  0.674  0.837  1.0
  Fe  Fe35  1  0.012  0.837  0.674  1.0
  Fe  Fe36  1  0.012  0.837  0.163  1.0
  Fe  Fe37  1  0.012  0.326  0.163  1.0
[/CIF]
.