The material structure described by Er(CuO2)2 crystallizes in the monoclinic C2/c space group. Er(1) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Er(1), one Cu(1), and one Cu(2) atom to form a mixture of corner and edge-sharing OEr2Cu2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Er(1), one Cu(1), and one Cu(2) atom to form a mixture of distorted corner and edge-sharing OEr2Cu2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er(CuO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.558
_cell_length_b   5.625
_cell_length_c   6.146
_cell_angle_alpha   116.266
_cell_angle_beta   115.910
_cell_angle_gamma   91.908
_symmetry_Int_Tables_number   1
_cell_volume   148.726
_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  0.875  0.125  0.750  1.0
  Er  Er1  1  0.125  0.875  0.250  1.0
  Cu  Cu2  1  0.500  0.000  0.000  1.0
  Cu  Cu3  1  0.500  0.500  0.000  1.0
  Cu  Cu4  1  0.000  0.500  0.500  1.0
  Cu  Cu5  1  0.500  0.500  0.500  1.0
  O  O6  1  0.724  0.525  0.858  1.0
  O  O7  1  0.134  0.834  0.858  1.0
  O  O8  1  0.276  0.475  0.142  1.0
  O  O9  1  0.866  0.166  0.142  1.0
  O  O10  1  0.536  0.133  0.352  1.0
  O  O11  1  0.816  0.719  0.352  1.0
  O  O12  1  0.184  0.281  0.648  1.0
  O  O13  1  0.464  0.867  0.648  1.0
[/CIF]
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The material structure described by Er(CuO2)2 crystallizes in the monoclinic C2/c space group. Er(1) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Er(1), one Cu(1), and one Cu(2) atom to form a mixture of corner and edge-sharing OEr2Cu2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Er(1), one Cu(1), and one Cu(2) atom to form a mixture of distorted corner and edge-sharing OEr2Cu2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Er(CuO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.558
_cell_length_b   5.625
_cell_length_c   6.146
_cell_angle_alpha   116.266
_cell_angle_beta   115.910
_cell_angle_gamma   91.908
_symmetry_Int_Tables_number   1
_cell_volume   148.726
_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  0.875  0.125  0.750  1.0
  Er  Er1  1  0.125  0.875  0.250  1.0
  Cu  Cu2  1  0.500  0.000  0.000  1.0
  Cu  Cu3  1  0.500  0.500  0.000  1.0
  Cu  Cu4  1  0.000  0.500  0.500  1.0
  Cu  Cu5  1  0.500  0.500  0.500  1.0
  O  O6  1  0.724  0.525  0.858  1.0
  O  O7  1  0.134  0.834  0.858  1.0
  O  O8  1  0.276  0.475  0.142  1.0
  O  O9  1  0.866  0.166  0.142  1.0
  O  O10  1  0.536  0.133  0.352  1.0
  O  O11  1  0.816  0.719  0.352  1.0
  O  O12  1  0.184  0.281  0.648  1.0
  O  O13  1  0.464  0.867  0.648  1.0
[/CIF]
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