The structure described by Cu5Er crystallizes in the cubic F-43m space group. Er(1) is bonded in a 16-coordinate geometry to four equivalent Cu(1) and twelve equivalent Cu(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Er(1) and twelve equivalent Cu(2) atoms to form distorted CuEr4Cu12 tetrahedra that share corners with twelve equivalent Cu(2)Er3Cu9 cuboctahedra, faces with twenty-eight equivalent Cu(2)Er3Cu9 cuboctahedra, and faces with twelve equivalent Cu(1)Er4Cu12 tetrahedra. In the second Cu site, Cu(2) is bonded to three equivalent Er(1), three equivalent Cu(1), and six equivalent Cu(2) atoms to form distorted CuEr3Cu9 cuboctahedra that share corners with eighteen equivalent Cu(2)Er3Cu9 cuboctahedra, corners with three equivalent Cu(1)Er4Cu12 tetrahedra, edges with six equivalent Cu(2)Er3Cu9 cuboctahedra, faces with eighteen equivalent Cu(2)Er3Cu9 cuboctahedra, and faces with seven equivalent Cu(1)Er4Cu12 tetrahedra. is represented by the CIF file [CIF]
data_ErCu5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.897
_cell_length_b   4.897
_cell_length_c   4.897
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   83.026
_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
  Er  Er0  1  0.000  0.000  0.000  1.0
  Cu  Cu1  1  0.250  0.250  0.250  1.0
  Cu  Cu2  1  0.624  0.624  0.624  1.0
  Cu  Cu3  1  0.624  0.624  0.128  1.0
  Cu  Cu4  1  0.128  0.624  0.624  1.0
  Cu  Cu5  1  0.624  0.128  0.624  1.0
[/CIF]
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The structure described by Cu5Er crystallizes in the cubic F-43m space group. Er(1) is bonded in a 16-coordinate geometry to four equivalent Cu(1) and twelve equivalent Cu(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Er(1) and twelve equivalent Cu(2) atoms to form distorted CuEr4Cu12 tetrahedra that share corners with twelve equivalent Cu(2)Er3Cu9 cuboctahedra, faces with twenty-eight equivalent Cu(2)Er3Cu9 cuboctahedra, and faces with twelve equivalent Cu(1)Er4Cu12 tetrahedra. In the second Cu site, Cu(2) is bonded to three equivalent Er(1), three equivalent Cu(1), and six equivalent Cu(2) atoms to form distorted CuEr3Cu9 cuboctahedra that share corners with eighteen equivalent Cu(2)Er3Cu9 cuboctahedra, corners with three equivalent Cu(1)Er4Cu12 tetrahedra, edges with six equivalent Cu(2)Er3Cu9 cuboctahedra, faces with eighteen equivalent Cu(2)Er3Cu9 cuboctahedra, and faces with seven equivalent Cu(1)Er4Cu12 tetrahedra. is represented by the CIF file [CIF]
data_ErCu5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.897
_cell_length_b   4.897
_cell_length_c   4.897
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   83.026
_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
  Er  Er0  1  0.000  0.000  0.000  1.0
  Cu  Cu1  1  0.250  0.250  0.250  1.0
  Cu  Cu2  1  0.624  0.624  0.624  1.0
  Cu  Cu3  1  0.624  0.624  0.128  1.0
  Cu  Cu4  1  0.128  0.624  0.624  1.0
  Cu  Cu5  1  0.624  0.128  0.624  1.0
[/CIF]
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