The compound described by Er5Ni2Bi crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to four equivalent Ni(1) and two equivalent Bi(1) atoms to form distorted ErNi4Bi2 octahedra that share corners with six equivalent Er(1)Ni4Bi2 octahedra, corners with sixteen equivalent Er(2)Ni3Bi2 square pyramids, and faces with eight equivalent Er(2)Ni3Bi2 square pyramids. The corner-sharing octahedral tilt angles range from 0-51°. In the second Er site, Er(2) is bonded to three equivalent Ni(1) and two equivalent Bi(1) atoms to form distorted ErNi3Bi2 square pyramids that share corners with four equivalent Er(1)Ni4Bi2 octahedra, corners with twelve equivalent Er(2)Ni3Bi2 square pyramids, edges with seven equivalent Er(2)Ni3Bi2 square pyramids, faces with two equivalent Er(1)Ni4Bi2 octahedra, and  a faceface with one Er(2)Ni3Bi2 square pyramid. The corner-sharing octahedral tilt angles range from 42-61°. Ni(1) is bonded in a 8-coordinate geometry to two equivalent Er(1) and six equivalent Er(2) atoms. Bi(1) is bonded in a distorted q6 geometry to two equivalent Er(1) and eight equivalent Er(2) atoms. is represented by the CIF file [CIF]
data_Er5Ni2Bi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.558
_cell_length_b   8.558
_cell_length_c   8.557
_cell_angle_alpha   127.511
_cell_angle_beta   127.514
_cell_angle_gamma   77.424
_symmetry_Int_Tables_number   1
_cell_volume   382.418
_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
  Er  Er0  1  1.000  1.000  1.000  1.0
  Er  Er1  1  0.500  0.500  1.000  1.0
  Er  Er2  1  0.789  0.289  0.811  1.0
  Er  Er3  1  0.211  0.711  0.189  1.0
  Er  Er4  1  0.478  0.978  0.189  1.0
  Er  Er5  1  0.288  0.478  0.500  1.0
  Er  Er6  1  0.022  0.212  0.500  1.0
  Er  Er7  1  0.522  0.022  0.811  1.0
  Er  Er8  1  0.711  0.522  0.500  1.0
  Er  Er9  1  0.978  0.789  0.500  1.0
  Ni  Ni10  1  0.132  0.632  0.764  1.0
  Ni  Ni11  1  0.868  0.368  0.236  1.0
  Ni  Ni12  1  0.632  0.868  0.500  1.0
  Ni  Ni13  1  0.368  0.132  0.500  1.0
  Bi  Bi14  1  0.250  0.250  1.000  1.0
  Bi  Bi15  1  0.750  0.750  1.000  1.0
[/CIF]
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The compound described by Er5Ni2Bi crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to four equivalent Ni(1) and two equivalent Bi(1) atoms to form distorted ErNi4Bi2 octahedra that share corners with six equivalent Er(1)Ni4Bi2 octahedra, corners with sixteen equivalent Er(2)Ni3Bi2 square pyramids, and faces with eight equivalent Er(2)Ni3Bi2 square pyramids. The corner-sharing octahedral tilt angles range from 0-51°. In the second Er site, Er(2) is bonded to three equivalent Ni(1) and two equivalent Bi(1) atoms to form distorted ErNi3Bi2 square pyramids that share corners with four equivalent Er(1)Ni4Bi2 octahedra, corners with twelve equivalent Er(2)Ni3Bi2 square pyramids, edges with seven equivalent Er(2)Ni3Bi2 square pyramids, faces with two equivalent Er(1)Ni4Bi2 octahedra, and  a faceface with one Er(2)Ni3Bi2 square pyramid. The corner-sharing octahedral tilt angles range from 42-61°. Ni(1) is bonded in a 8-coordinate geometry to two equivalent Er(1) and six equivalent Er(2) atoms. Bi(1) is bonded in a distorted q6 geometry to two equivalent Er(1) and eight equivalent Er(2) atoms. is represented by the CIF file [CIF]
data_Er5Ni2Bi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.558
_cell_length_b   8.558
_cell_length_c   8.557
_cell_angle_alpha   127.511
_cell_angle_beta   127.514
_cell_angle_gamma   77.424
_symmetry_Int_Tables_number   1
_cell_volume   382.418
_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
  Er  Er0  1  1.000  1.000  1.000  1.0
  Er  Er1  1  0.500  0.500  1.000  1.0
  Er  Er2  1  0.789  0.289  0.811  1.0
  Er  Er3  1  0.211  0.711  0.189  1.0
  Er  Er4  1  0.478  0.978  0.189  1.0
  Er  Er5  1  0.288  0.478  0.500  1.0
  Er  Er6  1  0.022  0.212  0.500  1.0
  Er  Er7  1  0.522  0.022  0.811  1.0
  Er  Er8  1  0.711  0.522  0.500  1.0
  Er  Er9  1  0.978  0.789  0.500  1.0
  Ni  Ni10  1  0.132  0.632  0.764  1.0
  Ni  Ni11  1  0.868  0.368  0.236  1.0
  Ni  Ni12  1  0.632  0.868  0.500  1.0
  Ni  Ni13  1  0.368  0.132  0.500  1.0
  Bi  Bi14  1  0.250  0.250  1.000  1.0
  Bi  Bi15  1  0.750  0.750  1.000  1.0
[/CIF]
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