The crystal structure described by Er3Pm is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded to eight Er(1,1) and four equivalent Pm(1) atoms to form ErPm4Er8 cuboctahedra that share corners with four equivalent Pm(1)Er12 cuboctahedra; corners with fourteen equivalent Er(1)Pm4Er8 cuboctahedra; edges with six equivalent Pm(1)Er12 cuboctahedra; edges with twelve Er(1,1)Pm4Er8 cuboctahedra; faces with four equivalent Pm(1)Er12 cuboctahedra; and faces with sixteen Er(1,1,1)Pm4Er8 cuboctahedra. In the second Er site, Er(1) is bonded to eight Er(1,1) and four equivalent Pm(1) atoms to form ErPm4Er8 cuboctahedra that share corners with four equivalent Pm(1)Er12 cuboctahedra; corners with fourteen Er(1,1,1)Pm4Er8 cuboctahedra; edges with six equivalent Pm(1)Er12 cuboctahedra; edges with twelve Er(1,1)Pm4Er8 cuboctahedra; faces with four equivalent Pm(1)Er12 cuboctahedra; and faces with sixteen Er(1,1,1)Pm4Er8 cuboctahedra. In the third Er site, Er(1) is bonded to eight Er(1,1) and four equivalent Pm(1) atoms to form ErPm4Er8 cuboctahedra that share corners with four equivalent Pm(1)Er12 cuboctahedra; corners with fourteen Er(1,1,1)Pm4Er8 cuboctahedra; edges with six equivalent Pm(1)Er12 cuboctahedra; edges with twelve Er(1,1)Pm4Er8 cuboctahedra; faces with four equivalent Pm(1)Er12 cuboctahedra; and faces with sixteen Er(1,1,1)Pm4Er8 cuboctahedra. Pm(1) is bonded to twelve Er(1,1,1) atoms to form PmEr12 cuboctahedra that share corners with six equivalent Pm(1)Er12 cuboctahedra; corners with twelve Er(1,1,1)Pm4Er8 cuboctahedra; edges with eighteen Er(1,1,1)Pm4Er8 cuboctahedra; faces with eight equivalent Pm(1)Er12 cuboctahedra; and faces with twelve Er(1,1,1)Pm4Er8 cuboctahedra. is represented by the CIF file [CIF]
data_PmEr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.198
_cell_length_b   7.198
_cell_length_c   5.756
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   258.255
_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
  Pm  Pm0  1  0.667  0.333  0.250  1.0
  Pm  Pm1  1  0.333  0.667  0.750  1.0
  Er  Er2  1  0.835  0.165  0.750  1.0
  Er  Er3  1  0.330  0.165  0.750  1.0
  Er  Er4  1  0.835  0.670  0.750  1.0
  Er  Er5  1  0.165  0.835  0.250  1.0
  Er  Er6  1  0.670  0.835  0.250  1.0
  Er  Er7  1  0.165  0.330  0.250  1.0
[/CIF]
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The crystal structure described by Er3Pm is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded to eight Er(1,1) and four equivalent Pm(1) atoms to form ErPm4Er8 cuboctahedra that share corners with four equivalent Pm(1)Er12 cuboctahedra; corners with fourteen equivalent Er(1)Pm4Er8 cuboctahedra; edges with six equivalent Pm(1)Er12 cuboctahedra; edges with twelve Er(1,1)Pm4Er8 cuboctahedra; faces with four equivalent Pm(1)Er12 cuboctahedra; and faces with sixteen Er(1,1,1)Pm4Er8 cuboctahedra. In the second Er site, Er(1) is bonded to eight Er(1,1) and four equivalent Pm(1) atoms to form ErPm4Er8 cuboctahedra that share corners with four equivalent Pm(1)Er12 cuboctahedra; corners with fourteen Er(1,1,1)Pm4Er8 cuboctahedra; edges with six equivalent Pm(1)Er12 cuboctahedra; edges with twelve Er(1,1)Pm4Er8 cuboctahedra; faces with four equivalent Pm(1)Er12 cuboctahedra; and faces with sixteen Er(1,1,1)Pm4Er8 cuboctahedra. In the third Er site, Er(1) is bonded to eight Er(1,1) and four equivalent Pm(1) atoms to form ErPm4Er8 cuboctahedra that share corners with four equivalent Pm(1)Er12 cuboctahedra; corners with fourteen Er(1,1,1)Pm4Er8 cuboctahedra; edges with six equivalent Pm(1)Er12 cuboctahedra; edges with twelve Er(1,1)Pm4Er8 cuboctahedra; faces with four equivalent Pm(1)Er12 cuboctahedra; and faces with sixteen Er(1,1,1)Pm4Er8 cuboctahedra. Pm(1) is bonded to twelve Er(1,1,1) atoms to form PmEr12 cuboctahedra that share corners with six equivalent Pm(1)Er12 cuboctahedra; corners with twelve Er(1,1,1)Pm4Er8 cuboctahedra; edges with eighteen Er(1,1,1)Pm4Er8 cuboctahedra; faces with eight equivalent Pm(1)Er12 cuboctahedra; and faces with twelve Er(1,1,1)Pm4Er8 cuboctahedra. is represented by the CIF file [CIF]
data_PmEr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.198
_cell_length_b   7.198
_cell_length_c   5.756
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   258.255
_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
  Pm  Pm0  1  0.667  0.333  0.250  1.0
  Pm  Pm1  1  0.333  0.667  0.750  1.0
  Er  Er2  1  0.835  0.165  0.750  1.0
  Er  Er3  1  0.330  0.165  0.750  1.0
  Er  Er4  1  0.835  0.670  0.750  1.0
  Er  Er5  1  0.165  0.835  0.250  1.0
  Er  Er6  1  0.670  0.835  0.250  1.0
  Er  Er7  1  0.165  0.330  0.250  1.0
[/CIF]
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