The material described by ErPr3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded to four equivalent Pr(2) and eight equivalent Pr(1) atoms to form ErPr12 cuboctahedra that share corners with four equivalent Er(1)Pr12 cuboctahedra, corners with eight equivalent Pr(2)Pr8Er4 cuboctahedra, edges with eight equivalent Er(1)Pr12 cuboctahedra, edges with sixteen equivalent Pr(1)Pr8Er4 cuboctahedra, faces with four equivalent Er(1)Pr12 cuboctahedra, faces with six equivalent Pr(2)Pr8Er4 cuboctahedra, and faces with eight equivalent Pr(1)Pr8Er4 cuboctahedra. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded to four equivalent Er(1), four equivalent Pr(1), and four equivalent Pr(2) atoms to form PrPr8Er4 cuboctahedra that share corners with twelve equivalent Pr(1)Pr8Er4 cuboctahedra, edges with eight equivalent Er(1)Pr12 cuboctahedra, edges with eight equivalent Pr(1)Pr8Er4 cuboctahedra, edges with eight equivalent Pr(2)Pr8Er4 cuboctahedra, faces with four equivalent Er(1)Pr12 cuboctahedra, faces with four equivalent Pr(2)Pr8Er4 cuboctahedra, and faces with ten equivalent Pr(1)Pr8Er4 cuboctahedra. In the second Pr site, Pr(2) is bonded to four equivalent Er(1) and eight equivalent Pr(1) atoms to form PrPr8Er4 cuboctahedra that share corners with four equivalent Pr(2)Pr8Er4 cuboctahedra, corners with eight equivalent Er(1)Pr12 cuboctahedra, edges with eight equivalent Pr(2)Pr8Er4 cuboctahedra, edges with sixteen equivalent Pr(1)Pr8Er4 cuboctahedra, faces with four equivalent Pr(2)Pr8Er4 cuboctahedra, faces with six equivalent Er(1)Pr12 cuboctahedra, and faces with eight equivalent Pr(1)Pr8Er4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Pr3Er
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.315
_cell_length_b   6.315
_cell_length_c   6.315
_cell_angle_alpha   131.236
_cell_angle_beta   131.236
_cell_angle_gamma   71.438
_symmetry_Int_Tables_number   1
_cell_volume   139.403
_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  0.750  0.250  0.500  1.0
  Pr  Pr1  1  0.250  0.750  0.500  1.0
  Pr  Pr2  1  0.500  0.500  0.000  1.0
  Er  Er3  1  0.000  0.000  0.000  1.0
[/CIF]
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The material described by ErPr3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded to four equivalent Pr(2) and eight equivalent Pr(1) atoms to form ErPr12 cuboctahedra that share corners with four equivalent Er(1)Pr12 cuboctahedra, corners with eight equivalent Pr(2)Pr8Er4 cuboctahedra, edges with eight equivalent Er(1)Pr12 cuboctahedra, edges with sixteen equivalent Pr(1)Pr8Er4 cuboctahedra, faces with four equivalent Er(1)Pr12 cuboctahedra, faces with six equivalent Pr(2)Pr8Er4 cuboctahedra, and faces with eight equivalent Pr(1)Pr8Er4 cuboctahedra. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded to four equivalent Er(1), four equivalent Pr(1), and four equivalent Pr(2) atoms to form PrPr8Er4 cuboctahedra that share corners with twelve equivalent Pr(1)Pr8Er4 cuboctahedra, edges with eight equivalent Er(1)Pr12 cuboctahedra, edges with eight equivalent Pr(1)Pr8Er4 cuboctahedra, edges with eight equivalent Pr(2)Pr8Er4 cuboctahedra, faces with four equivalent Er(1)Pr12 cuboctahedra, faces with four equivalent Pr(2)Pr8Er4 cuboctahedra, and faces with ten equivalent Pr(1)Pr8Er4 cuboctahedra. In the second Pr site, Pr(2) is bonded to four equivalent Er(1) and eight equivalent Pr(1) atoms to form PrPr8Er4 cuboctahedra that share corners with four equivalent Pr(2)Pr8Er4 cuboctahedra, corners with eight equivalent Er(1)Pr12 cuboctahedra, edges with eight equivalent Pr(2)Pr8Er4 cuboctahedra, edges with sixteen equivalent Pr(1)Pr8Er4 cuboctahedra, faces with four equivalent Pr(2)Pr8Er4 cuboctahedra, faces with six equivalent Er(1)Pr12 cuboctahedra, and faces with eight equivalent Pr(1)Pr8Er4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Pr3Er
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.315
_cell_length_b   6.315
_cell_length_c   6.315
_cell_angle_alpha   131.236
_cell_angle_beta   131.236
_cell_angle_gamma   71.438
_symmetry_Int_Tables_number   1
_cell_volume   139.403
_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  0.750  0.250  0.500  1.0
  Pr  Pr1  1  0.250  0.750  0.500  1.0
  Pr  Pr2  1  0.500  0.500  0.000  1.0
  Er  Er3  1  0.000  0.000  0.000  1.0
[/CIF]
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