The material structure described by ErPrCo17 crystallizes in the trigonal R3m space group. Er(1) is bonded in a 19-coordinate geometry to one Co(5), three equivalent Co(2), three equivalent Co(4), six equivalent Co(1), and six equivalent Co(3) atoms. Pr(1) is bonded in a 19-coordinate geometry to one Co(6), three equivalent Co(3), three equivalent Co(4), six equivalent Co(1), and six equivalent Co(2) atoms. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one Er(1), one Pr(1), one Co(5), one Co(6), two equivalent Co(1), two equivalent Co(2), two equivalent Co(3), and two equivalent Co(4) atoms to form distorted CoPrErCo10 cuboctahedra that share corners with four equivalent Co(2)Pr2ErCo9 cuboctahedra, corners with four equivalent Co(3)PrEr2Co9 cuboctahedra, corners with four equivalent Co(4)PrErCo10 cuboctahedra, corners with twelve equivalent Co(1)PrErCo10 cuboctahedra,  an edgeedge with one Co(2)Pr2ErCo9 cuboctahedra,  an edgeedge with one Co(3)PrEr2Co9 cuboctahedra,  an edgeedge with one Co(1)PrErCo10 cuboctahedra, edges with two equivalent Co(4)PrErCo10 cuboctahedra, faces with four equivalent Co(4)PrErCo10 cuboctahedra, faces with five equivalent Co(2)Pr2ErCo9 cuboctahedra, faces with five equivalent Co(3)PrEr2Co9 cuboctahedra, and faces with seven equivalent Co(1)PrErCo10 cuboctahedra. In the second Co site, Co(2) is bonded to one Er(1), two equivalent Pr(1), one Co(6), two equivalent Co(3), two equivalent Co(4), and four equivalent Co(1) atoms to form CoPr2ErCo9 cuboctahedra that share corners with two equivalent Co(2)Pr2ErCo9 cuboctahedra, corners with five equivalent Co(4)PrErCo10 cuboctahedra, corners with eight equivalent Co(3)PrEr2Co9 cuboctahedra, corners with eight equivalent Co(1)PrErCo10 cuboctahedra,  an edgeedge with one Co(3)PrEr2Co9 cuboctahedra, edges with two equivalent Co(1)PrErCo10 cuboctahedra, edges with three equivalent Co(4)PrErCo10 cuboctahedra, edges with four equivalent Co(2)Pr2ErCo9 cuboctahedra, faces with three equivalent Co(3)PrEr2Co9 cuboctahedra, faces with three equivalent Co(4)PrErCo10 cuboctahedra, faces with four equivalent Co(2)Pr2ErCo9 cuboctahedra, and faces with ten equivalent Co(1)PrErCo10 cuboctahedra. In the third Co site, Co(3) is bonded to two equivalent Er(1), one Pr(1), one Co(5), two equivalent Co(2), two equivalent Co(4), and four equivalent Co(1) atoms to form CoPrEr2Co9 cuboctahedra that share corners with two equivalent Co(3)PrEr2Co9 cuboctahedra, corners with five equivalent Co(4)PrErCo10 cuboctahedra, corners with eight equivalent Co(2)Pr2ErCo9 cuboctahedra, corners with eight equivalent Co(1)PrErCo10 cuboctahedra,  an edgeedge with one Co(2)Pr2ErCo9 cuboctahedra, edges with two equivalent Co(1)PrErCo10 cuboctahedra, edges with three equivalent Co(4)PrErCo10 cuboctahedra, edges with four equivalent Co(3)PrEr2Co9 cuboctahedra, faces with three equivalent Co(2)Pr2ErCo9 cuboctahedra, faces with three equivalent Co(4)PrErCo10 cuboctahedra, faces with four equivalent Co(3)PrEr2Co9 cuboctahedra, and faces with ten equivalent Co(1)PrErCo10 cuboctahedra. In the fourth Co site, Co(4) is bonded to one Er(1), one Pr(1), one Co(5), one Co(6), two equivalent Co(2), two equivalent Co(3), and four equivalent Co(1) atoms to form distorted CoPrErCo10 cuboctahedra that share corners with four equivalent Co(4)PrErCo10 cuboctahedra, corners with five equivalent Co(2)Pr2ErCo9 cuboctahedra, corners with five equivalent Co(3)PrEr2Co9 cuboctahedra, corners with eight equivalent Co(1)PrErCo10 cuboctahedra, edges with three equivalent Co(2)Pr2ErCo9 cuboctahedra, edges with three equivalent Co(3)PrEr2Co9 cuboctahedra, edges with four equivalent Co(1)PrErCo10 cuboctahedra, faces with three equivalent Co(2)Pr2ErCo9 cuboctahedra, faces with three equivalent Co(3)PrEr2Co9 cuboctahedra, faces with four equivalent Co(4)PrErCo10 cuboctahedra, and faces with eight equivalent Co(1)PrErCo10 cuboctahedra. In the fifth Co site, Co(5) is bonded in a 14-coordinate geometry to one Er(1), one Co(6), three equivalent Co(3), three equivalent Co(4), and six equivalent Co(1) atoms. In the sixth Co site, Co(6) is bonded in a 14-coordinate geometry to one Pr(1), one Co(5), three equivalent Co(2), three equivalent Co(4), and six equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_PrErCo17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.293
_cell_length_b   6.293
_cell_length_c   6.293
_cell_angle_alpha   83.271
_cell_angle_beta   83.271
_cell_angle_gamma   83.271
_symmetry_Int_Tables_number   1
_cell_volume   244.432
_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
  Pr  Pr0  1  0.653  0.653  0.653  1.0
  Er  Er1  1  0.343  0.343  0.343  1.0
  Co  Co2  1  0.286  0.002  0.714  1.0
  Co  Co3  1  0.002  0.714  0.286  1.0
  Co  Co4  1  0.714  0.286  0.002  1.0
  Co  Co5  1  0.002  0.286  0.714  1.0
  Co  Co6  1  0.286  0.714  0.002  1.0
  Co  Co7  1  0.714  0.002  0.286  1.0
  Co  Co8  1  0.654  0.151  0.654  1.0
  Co  Co9  1  0.151  0.654  0.654  1.0
  Co  Co10  1  0.654  0.654  0.151  1.0
  Co  Co11  1  0.343  0.851  0.343  1.0
  Co  Co12  1  0.851  0.343  0.343  1.0
  Co  Co13  1  0.343  0.343  0.851  1.0
  Co  Co14  1  0.002  0.499  0.002  1.0
  Co  Co15  1  0.499  0.002  0.002  1.0
  Co  Co16  1  0.002  0.002  0.499  1.0
  Co  Co17  1  0.098  0.098  0.098  1.0
  Co  Co18  1  0.905  0.905  0.905  1.0
[/CIF]
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The material structure described by ErPrCo17 crystallizes in the trigonal R3m space group. Er(1) is bonded in a 19-coordinate geometry to one Co(5), three equivalent Co(2), three equivalent Co(4), six equivalent Co(1), and six equivalent Co(3) atoms. Pr(1) is bonded in a 19-coordinate geometry to one Co(6), three equivalent Co(3), three equivalent Co(4), six equivalent Co(1), and six equivalent Co(2) atoms. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one Er(1), one Pr(1), one Co(5), one Co(6), two equivalent Co(1), two equivalent Co(2), two equivalent Co(3), and two equivalent Co(4) atoms to form distorted CoPrErCo10 cuboctahedra that share corners with four equivalent Co(2)Pr2ErCo9 cuboctahedra, corners with four equivalent Co(3)PrEr2Co9 cuboctahedra, corners with four equivalent Co(4)PrErCo10 cuboctahedra, corners with twelve equivalent Co(1)PrErCo10 cuboctahedra,  an edgeedge with one Co(2)Pr2ErCo9 cuboctahedra,  an edgeedge with one Co(3)PrEr2Co9 cuboctahedra,  an edgeedge with one Co(1)PrErCo10 cuboctahedra, edges with two equivalent Co(4)PrErCo10 cuboctahedra, faces with four equivalent Co(4)PrErCo10 cuboctahedra, faces with five equivalent Co(2)Pr2ErCo9 cuboctahedra, faces with five equivalent Co(3)PrEr2Co9 cuboctahedra, and faces with seven equivalent Co(1)PrErCo10 cuboctahedra. In the second Co site, Co(2) is bonded to one Er(1), two equivalent Pr(1), one Co(6), two equivalent Co(3), two equivalent Co(4), and four equivalent Co(1) atoms to form CoPr2ErCo9 cuboctahedra that share corners with two equivalent Co(2)Pr2ErCo9 cuboctahedra, corners with five equivalent Co(4)PrErCo10 cuboctahedra, corners with eight equivalent Co(3)PrEr2Co9 cuboctahedra, corners with eight equivalent Co(1)PrErCo10 cuboctahedra,  an edgeedge with one Co(3)PrEr2Co9 cuboctahedra, edges with two equivalent Co(1)PrErCo10 cuboctahedra, edges with three equivalent Co(4)PrErCo10 cuboctahedra, edges with four equivalent Co(2)Pr2ErCo9 cuboctahedra, faces with three equivalent Co(3)PrEr2Co9 cuboctahedra, faces with three equivalent Co(4)PrErCo10 cuboctahedra, faces with four equivalent Co(2)Pr2ErCo9 cuboctahedra, and faces with ten equivalent Co(1)PrErCo10 cuboctahedra. In the third Co site, Co(3) is bonded to two equivalent Er(1), one Pr(1), one Co(5), two equivalent Co(2), two equivalent Co(4), and four equivalent Co(1) atoms to form CoPrEr2Co9 cuboctahedra that share corners with two equivalent Co(3)PrEr2Co9 cuboctahedra, corners with five equivalent Co(4)PrErCo10 cuboctahedra, corners with eight equivalent Co(2)Pr2ErCo9 cuboctahedra, corners with eight equivalent Co(1)PrErCo10 cuboctahedra,  an edgeedge with one Co(2)Pr2ErCo9 cuboctahedra, edges with two equivalent Co(1)PrErCo10 cuboctahedra, edges with three equivalent Co(4)PrErCo10 cuboctahedra, edges with four equivalent Co(3)PrEr2Co9 cuboctahedra, faces with three equivalent Co(2)Pr2ErCo9 cuboctahedra, faces with three equivalent Co(4)PrErCo10 cuboctahedra, faces with four equivalent Co(3)PrEr2Co9 cuboctahedra, and faces with ten equivalent Co(1)PrErCo10 cuboctahedra. In the fourth Co site, Co(4) is bonded to one Er(1), one Pr(1), one Co(5), one Co(6), two equivalent Co(2), two equivalent Co(3), and four equivalent Co(1) atoms to form distorted CoPrErCo10 cuboctahedra that share corners with four equivalent Co(4)PrErCo10 cuboctahedra, corners with five equivalent Co(2)Pr2ErCo9 cuboctahedra, corners with five equivalent Co(3)PrEr2Co9 cuboctahedra, corners with eight equivalent Co(1)PrErCo10 cuboctahedra, edges with three equivalent Co(2)Pr2ErCo9 cuboctahedra, edges with three equivalent Co(3)PrEr2Co9 cuboctahedra, edges with four equivalent Co(1)PrErCo10 cuboctahedra, faces with three equivalent Co(2)Pr2ErCo9 cuboctahedra, faces with three equivalent Co(3)PrEr2Co9 cuboctahedra, faces with four equivalent Co(4)PrErCo10 cuboctahedra, and faces with eight equivalent Co(1)PrErCo10 cuboctahedra. In the fifth Co site, Co(5) is bonded in a 14-coordinate geometry to one Er(1), one Co(6), three equivalent Co(3), three equivalent Co(4), and six equivalent Co(1) atoms. In the sixth Co site, Co(6) is bonded in a 14-coordinate geometry to one Pr(1), one Co(5), three equivalent Co(2), three equivalent Co(4), and six equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_PrErCo17
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.293
_cell_length_b   6.293
_cell_length_c   6.293
_cell_angle_alpha   83.271
_cell_angle_beta   83.271
_cell_angle_gamma   83.271
_symmetry_Int_Tables_number   1
_cell_volume   244.432
_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
  Pr  Pr0  1  0.653  0.653  0.653  1.0
  Er  Er1  1  0.343  0.343  0.343  1.0
  Co  Co2  1  0.286  0.002  0.714  1.0
  Co  Co3  1  0.002  0.714  0.286  1.0
  Co  Co4  1  0.714  0.286  0.002  1.0
  Co  Co5  1  0.002  0.286  0.714  1.0
  Co  Co6  1  0.286  0.714  0.002  1.0
  Co  Co7  1  0.714  0.002  0.286  1.0
  Co  Co8  1  0.654  0.151  0.654  1.0
  Co  Co9  1  0.151  0.654  0.654  1.0
  Co  Co10  1  0.654  0.654  0.151  1.0
  Co  Co11  1  0.343  0.851  0.343  1.0
  Co  Co12  1  0.851  0.343  0.343  1.0
  Co  Co13  1  0.343  0.343  0.851  1.0
  Co  Co14  1  0.002  0.499  0.002  1.0
  Co  Co15  1  0.499  0.002  0.002  1.0
  Co  Co16  1  0.002  0.002  0.499  1.0
  Co  Co17  1  0.098  0.098  0.098  1.0
  Co  Co18  1  0.905  0.905  0.905  1.0
[/CIF]
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