The material described by Er3Cu4Ge4 crystallizes in the triclinic P-1 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 12-coordinate geometry to three equivalent Cu(1), three equivalent Cu(2), two equivalent Ge(2), and four equivalent Ge(1) atoms. In the second Er site, Er(2) is bonded to two equivalent Ge(2) and four equivalent Ge(1) atoms to form distorted edge-sharing ErGe6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 8-coordinate geometry to three equivalent Er(1), one Cu(2), one Ge(1), and three equivalent Ge(2) atoms. In the second Cu site, Cu(2) is bonded in a 8-coordinate geometry to three equivalent Er(1), one Cu(1), one Ge(1), and three equivalent Ge(2) atoms. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Er(2), four equivalent Er(1), one Cu(1), one Cu(2), and one Ge(1) atom. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to one Er(2), two equivalent Er(1), three equivalent Cu(1), and three equivalent Cu(2) atoms. is represented by the CIF file [CIF]
data_Er3(CuGe)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.142
_cell_length_b   6.583
_cell_length_c   7.891
_cell_angle_alpha   114.657
_cell_angle_beta   105.217
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   187.202
_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  0.870  0.870  0.739  1.0
  Er  Er1  1  0.130  0.130  0.261  1.0
  Er  Er2  1  0.000  0.500  0.000  1.0
  Cu  Cu3  1  0.329  0.141  0.661  1.0
  Cu  Cu4  1  0.329  0.520  0.660  1.0
  Cu  Cu5  1  0.671  0.859  0.339  1.0
  Cu  Cu6  1  0.671  0.480  0.340  1.0
  Ge  Ge7  1  0.500  0.808  1.000  1.0
  Ge  Ge8  1  0.783  0.283  0.567  1.0
  Ge  Ge9  1  0.217  0.717  0.433  1.0
  Ge  Ge10  1  0.500  0.192  0.000  1.0
[/CIF]
.
The material described by Er3Cu4Ge4 crystallizes in the triclinic P-1 space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 12-coordinate geometry to three equivalent Cu(1), three equivalent Cu(2), two equivalent Ge(2), and four equivalent Ge(1) atoms. In the second Er site, Er(2) is bonded to two equivalent Ge(2) and four equivalent Ge(1) atoms to form distorted edge-sharing ErGe6 octahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 8-coordinate geometry to three equivalent Er(1), one Cu(2), one Ge(1), and three equivalent Ge(2) atoms. In the second Cu site, Cu(2) is bonded in a 8-coordinate geometry to three equivalent Er(1), one Cu(1), one Ge(1), and three equivalent Ge(2) atoms. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to two equivalent Er(2), four equivalent Er(1), one Cu(1), one Cu(2), and one Ge(1) atom. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to one Er(2), two equivalent Er(1), three equivalent Cu(1), and three equivalent Cu(2) atoms. is represented by the CIF file [CIF]
data_Er3(CuGe)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.142
_cell_length_b   6.583
_cell_length_c   7.891
_cell_angle_alpha   114.657
_cell_angle_beta   105.217
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   187.202
_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  0.870  0.870  0.739  1.0
  Er  Er1  1  0.130  0.130  0.261  1.0
  Er  Er2  1  0.000  0.500  0.000  1.0
  Cu  Cu3  1  0.329  0.141  0.661  1.0
  Cu  Cu4  1  0.329  0.520  0.660  1.0
  Cu  Cu5  1  0.671  0.859  0.339  1.0
  Cu  Cu6  1  0.671  0.480  0.340  1.0
  Ge  Ge7  1  0.500  0.808  1.000  1.0
  Ge  Ge8  1  0.783  0.283  0.567  1.0
  Ge  Ge9  1  0.217  0.717  0.433  1.0
  Ge  Ge10  1  0.500  0.192  0.000  1.0
[/CIF]
.