The material structure described by ErCu(WO4)2 crystallizes in the triclinic P-1 space group. Er(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form ErO6 octahedra that share corners with eight equivalent W(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-56°. W(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted WO6 octahedra that share corners with four equivalent Er(1)O6 octahedra and edges with two equivalent W(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-56°. Cu(1) is bonded in a linear geometry to two equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one W(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one W(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent W(1) and one Cu(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Er(1) and two equivalent W(1) atoms. is represented by the CIF file [CIF]
data_ErCu(WO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.140
_cell_length_b   6.060
_cell_length_c   6.084
_cell_angle_alpha   108.904
_cell_angle_beta   91.439
_cell_angle_gamma   114.401
_symmetry_Int_Tables_number   1
_cell_volume   160.454
_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  0.500  0.000  1.0
  Cu  Cu1  1  0.500  0.500  0.500  1.0
  W  W2  1  0.748  0.010  0.328  1.0
  W  W3  1  0.252  0.990  0.672  1.0
  O  O4  1  0.478  0.756  0.071  1.0
  O  O5  1  0.980  0.244  0.206  1.0
  O  O6  1  0.459  0.796  0.525  1.0
  O  O7  1  0.026  0.192  0.668  1.0
  O  O8  1  0.020  0.756  0.794  1.0
  O  O9  1  0.522  0.244  0.929  1.0
  O  O10  1  0.541  0.204  0.475  1.0
  O  O11  1  0.974  0.808  0.332  1.0
[/CIF]
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The material structure described by ErCu(WO4)2 crystallizes in the triclinic P-1 space group. Er(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form ErO6 octahedra that share corners with eight equivalent W(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-56°. W(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted WO6 octahedra that share corners with four equivalent Er(1)O6 octahedra and edges with two equivalent W(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-56°. Cu(1) is bonded in a linear geometry to two equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one W(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Er(1) and one W(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent W(1) and one Cu(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Er(1) and two equivalent W(1) atoms. is represented by the CIF file [CIF]
data_ErCu(WO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.140
_cell_length_b   6.060
_cell_length_c   6.084
_cell_angle_alpha   108.904
_cell_angle_beta   91.439
_cell_angle_gamma   114.401
_symmetry_Int_Tables_number   1
_cell_volume   160.454
_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  0.500  0.000  1.0
  Cu  Cu1  1  0.500  0.500  0.500  1.0
  W  W2  1  0.748  0.010  0.328  1.0
  W  W3  1  0.252  0.990  0.672  1.0
  O  O4  1  0.478  0.756  0.071  1.0
  O  O5  1  0.980  0.244  0.206  1.0
  O  O6  1  0.459  0.796  0.525  1.0
  O  O7  1  0.026  0.192  0.668  1.0
  O  O8  1  0.020  0.756  0.794  1.0
  O  O9  1  0.522  0.244  0.929  1.0
  O  O10  1  0.541  0.204  0.475  1.0
  O  O11  1  0.974  0.808  0.332  1.0
[/CIF]
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