The compound described by ErCu2Ge2 crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded in a 16-coordinate geometry to eight equivalent Cu(1) and eight equivalent Ge(1) atoms. Cu(1) is bonded to four equivalent Er(1) and four equivalent Ge(1) atoms to form a mixture of distorted face, edge, and corner-sharing CuEr4Ge4 tetrahedra. Ge(1) is bonded in a 9-coordinate geometry to four equivalent Er(1), four equivalent Cu(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_Er(CuGe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.857
_cell_length_b   5.857
_cell_length_c   5.857
_cell_angle_alpha   140.168
_cell_angle_beta   140.168
_cell_angle_gamma   57.598
_symmetry_Int_Tables_number   1
_cell_volume   81.736
_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  0.750  0.500  1.0
  Cu  Cu2  1  0.750  0.250  0.500  1.0
  Ge  Ge3  1  0.618  0.618  0.000  1.0
  Ge  Ge4  1  0.382  0.382  0.000  1.0
[/CIF]
.
The compound described by ErCu2Ge2 crystallizes in the tetragonal I4/mmm space group. Er(1) is bonded in a 16-coordinate geometry to eight equivalent Cu(1) and eight equivalent Ge(1) atoms. Cu(1) is bonded to four equivalent Er(1) and four equivalent Ge(1) atoms to form a mixture of distorted face, edge, and corner-sharing CuEr4Ge4 tetrahedra. Ge(1) is bonded in a 9-coordinate geometry to four equivalent Er(1), four equivalent Cu(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_Er(CuGe)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.857
_cell_length_b   5.857
_cell_length_c   5.857
_cell_angle_alpha   140.168
_cell_angle_beta   140.168
_cell_angle_gamma   57.598
_symmetry_Int_Tables_number   1
_cell_volume   81.736
_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  0.750  0.500  1.0
  Cu  Cu2  1  0.750  0.250  0.500  1.0
  Ge  Ge3  1  0.618  0.618  0.000  1.0
  Ge  Ge4  1  0.382  0.382  0.000  1.0
[/CIF]
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