The compound described by Er3Pr is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to eight Er(1,1) and four equivalent Pr(1) atoms to form ErPr4Er8 cuboctahedra that share corners with four equivalent Pr(1)Er12 cuboctahedra; corners with fourteen equivalent Er(1)Pr4Er8 cuboctahedra; edges with six equivalent Pr(1)Er12 cuboctahedra; edges with twelve Er(1,1)Pr4Er8 cuboctahedra; faces with four equivalent Pr(1)Er12 cuboctahedra; and faces with sixteen Er(1,1)Pr4Er8 cuboctahedra. In the second Er site, Er(1) is bonded to eight equivalent Er(1) and four equivalent Pr(1) atoms to form ErPr4Er8 cuboctahedra that share corners with four equivalent Pr(1)Er12 cuboctahedra; corners with fourteen Er(1,1)Pr4Er8 cuboctahedra; edges with six equivalent Pr(1)Er12 cuboctahedra; edges with twelve equivalent Er(1)Pr4Er8 cuboctahedra; faces with four equivalent Pr(1)Er12 cuboctahedra; and faces with sixteen Er(1,1)Pr4Er8 cuboctahedra. Pr(1) is bonded to twelve Er(1,1) atoms to form PrEr12 cuboctahedra that share corners with six equivalent Pr(1)Er12 cuboctahedra; corners with twelve Er(1,1)Pr4Er8 cuboctahedra; edges with eighteen Er(1,1)Pr4Er8 cuboctahedra; faces with eight equivalent Pr(1)Er12 cuboctahedra; and faces with twelve Er(1,1)Pr4Er8 cuboctahedra. is represented by the CIF file [CIF]
data_PrEr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.262
_cell_length_b   7.262
_cell_length_c   5.722
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   261.336
_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
  Pr  Pr0  1  0.333  0.667  0.750  1.0
  Pr  Pr1  1  0.667  0.333  0.250  1.0
  Er  Er2  1  0.165  0.329  0.250  1.0
  Er  Er3  1  0.671  0.835  0.250  1.0
  Er  Er4  1  0.165  0.835  0.250  1.0
  Er  Er5  1  0.835  0.671  0.750  1.0
  Er  Er6  1  0.329  0.165  0.750  1.0
  Er  Er7  1  0.835  0.165  0.750  1.0
[/CIF]
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The compound described by Er3Pr is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to eight Er(1,1) and four equivalent Pr(1) atoms to form ErPr4Er8 cuboctahedra that share corners with four equivalent Pr(1)Er12 cuboctahedra; corners with fourteen equivalent Er(1)Pr4Er8 cuboctahedra; edges with six equivalent Pr(1)Er12 cuboctahedra; edges with twelve Er(1,1)Pr4Er8 cuboctahedra; faces with four equivalent Pr(1)Er12 cuboctahedra; and faces with sixteen Er(1,1)Pr4Er8 cuboctahedra. In the second Er site, Er(1) is bonded to eight equivalent Er(1) and four equivalent Pr(1) atoms to form ErPr4Er8 cuboctahedra that share corners with four equivalent Pr(1)Er12 cuboctahedra; corners with fourteen Er(1,1)Pr4Er8 cuboctahedra; edges with six equivalent Pr(1)Er12 cuboctahedra; edges with twelve equivalent Er(1)Pr4Er8 cuboctahedra; faces with four equivalent Pr(1)Er12 cuboctahedra; and faces with sixteen Er(1,1)Pr4Er8 cuboctahedra. Pr(1) is bonded to twelve Er(1,1) atoms to form PrEr12 cuboctahedra that share corners with six equivalent Pr(1)Er12 cuboctahedra; corners with twelve Er(1,1)Pr4Er8 cuboctahedra; edges with eighteen Er(1,1)Pr4Er8 cuboctahedra; faces with eight equivalent Pr(1)Er12 cuboctahedra; and faces with twelve Er(1,1)Pr4Er8 cuboctahedra. is represented by the CIF file [CIF]
data_PrEr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.262
_cell_length_b   7.262
_cell_length_c   5.722
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   261.336
_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
  Pr  Pr0  1  0.333  0.667  0.750  1.0
  Pr  Pr1  1  0.667  0.333  0.250  1.0
  Er  Er2  1  0.165  0.329  0.250  1.0
  Er  Er3  1  0.671  0.835  0.250  1.0
  Er  Er4  1  0.165  0.835  0.250  1.0
  Er  Er5  1  0.835  0.671  0.750  1.0
  Er  Er6  1  0.329  0.165  0.750  1.0
  Er  Er7  1  0.835  0.165  0.750  1.0
[/CIF]
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