The material described by Er3Pr is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to four equivalent Er(1), four equivalent Er(2), and four equivalent Pr(1) atoms to form ErPr4Er8 cuboctahedra that share corners with twelve equivalent Er(1)Pr4Er8 cuboctahedra, edges with eight equivalent Er(1)Pr4Er8 cuboctahedra, edges with eight equivalent Er(2)Pr4Er8 cuboctahedra, edges with eight equivalent Pr(1)Er12 cuboctahedra, faces with four equivalent Er(2)Pr4Er8 cuboctahedra, faces with four equivalent Pr(1)Er12 cuboctahedra, and faces with ten equivalent Er(1)Pr4Er8 cuboctahedra. In the second Er site, Er(2) is bonded to eight equivalent Er(1) and four equivalent Pr(1) atoms to form ErPr4Er8 cuboctahedra that share corners with four equivalent Er(2)Pr4Er8 cuboctahedra, corners with eight equivalent Pr(1)Er12 cuboctahedra, edges with eight equivalent Er(2)Pr4Er8 cuboctahedra, edges with sixteen equivalent Er(1)Pr4Er8 cuboctahedra, faces with four equivalent Er(2)Pr4Er8 cuboctahedra, faces with six equivalent Pr(1)Er12 cuboctahedra, and faces with eight equivalent Er(1)Pr4Er8 cuboctahedra. Pr(1) is bonded to four equivalent Er(2) and eight equivalent Er(1) atoms to form PrEr12 cuboctahedra that share corners with four equivalent Pr(1)Er12 cuboctahedra, corners with eight equivalent Er(2)Pr4Er8 cuboctahedra, edges with eight equivalent Pr(1)Er12 cuboctahedra, edges with sixteen equivalent Er(1)Pr4Er8 cuboctahedra, faces with four equivalent Pr(1)Er12 cuboctahedra, faces with six equivalent Er(2)Pr4Er8 cuboctahedra, and faces with eight equivalent Er(1)Pr4Er8 cuboctahedra. is represented by the CIF card [CIF]
data_PrEr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.134
_cell_length_b   6.134
_cell_length_c   6.134
_cell_angle_alpha   131.206
_cell_angle_beta   131.206
_cell_angle_gamma   71.486
_symmetry_Int_Tables_number   1
_cell_volume   127.844
_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  0.000  0.000  0.000  1.0
  Er  Er1  1  0.750  0.250  0.500  1.0
  Er  Er2  1  0.250  0.750  0.500  1.0
  Er  Er3  1  0.500  0.500  0.000  1.0
[/CIF]
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The material described by Er3Pr is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to four equivalent Er(1), four equivalent Er(2), and four equivalent Pr(1) atoms to form ErPr4Er8 cuboctahedra that share corners with twelve equivalent Er(1)Pr4Er8 cuboctahedra, edges with eight equivalent Er(1)Pr4Er8 cuboctahedra, edges with eight equivalent Er(2)Pr4Er8 cuboctahedra, edges with eight equivalent Pr(1)Er12 cuboctahedra, faces with four equivalent Er(2)Pr4Er8 cuboctahedra, faces with four equivalent Pr(1)Er12 cuboctahedra, and faces with ten equivalent Er(1)Pr4Er8 cuboctahedra. In the second Er site, Er(2) is bonded to eight equivalent Er(1) and four equivalent Pr(1) atoms to form ErPr4Er8 cuboctahedra that share corners with four equivalent Er(2)Pr4Er8 cuboctahedra, corners with eight equivalent Pr(1)Er12 cuboctahedra, edges with eight equivalent Er(2)Pr4Er8 cuboctahedra, edges with sixteen equivalent Er(1)Pr4Er8 cuboctahedra, faces with four equivalent Er(2)Pr4Er8 cuboctahedra, faces with six equivalent Pr(1)Er12 cuboctahedra, and faces with eight equivalent Er(1)Pr4Er8 cuboctahedra. Pr(1) is bonded to four equivalent Er(2) and eight equivalent Er(1) atoms to form PrEr12 cuboctahedra that share corners with four equivalent Pr(1)Er12 cuboctahedra, corners with eight equivalent Er(2)Pr4Er8 cuboctahedra, edges with eight equivalent Pr(1)Er12 cuboctahedra, edges with sixteen equivalent Er(1)Pr4Er8 cuboctahedra, faces with four equivalent Pr(1)Er12 cuboctahedra, faces with six equivalent Er(2)Pr4Er8 cuboctahedra, and faces with eight equivalent Er(1)Pr4Er8 cuboctahedra. is represented by the CIF card [CIF]
data_PrEr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.134
_cell_length_b   6.134
_cell_length_c   6.134
_cell_angle_alpha   131.206
_cell_angle_beta   131.206
_cell_angle_gamma   71.486
_symmetry_Int_Tables_number   1
_cell_volume   127.844
_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  0.000  0.000  0.000  1.0
  Er  Er1  1  0.750  0.250  0.500  1.0
  Er  Er2  1  0.250  0.750  0.500  1.0
  Er  Er3  1  0.500  0.500  0.000  1.0
[/CIF]
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