The crystal structure described by KEr(WO4)2 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. Er(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. W(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing WO6 octahedra. The corner-sharing octahedral tilt angles are 42°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent K(1) and two equivalent W(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to one K(1), one Er(1), and one W(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one K(1), one Er(1), and one W(1) atom. In the fourth O site, O(4) is bonded to one K(1), one Er(1), and two equivalent W(1) atoms to form a mixture of distorted edge and corner-sharing OKErW2 tetrahedra. is represented by the CIF file [CIF]
data_KEr(WO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.602
_cell_length_b   7.602
_cell_length_c   7.451
_cell_angle_alpha   62.091
_cell_angle_beta   62.091
_cell_angle_gamma   87.905
_symmetry_Int_Tables_number   1
_cell_volume   326.975
_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
  K  K0  1  0.208  0.792  0.750  1.0
  K  K1  1  0.792  0.208  0.250  1.0
  Er  Er2  1  0.224  0.776  0.250  1.0
  Er  Er3  1  0.776  0.224  0.750  1.0
  W  W4  1  0.693  0.701  0.283  1.0
  W  W5  1  0.701  0.693  0.783  1.0
  W  W6  1  0.307  0.299  0.717  1.0
  W  W7  1  0.299  0.307  0.217  1.0
  O  O8  1  0.244  0.377  0.944  1.0
  O  O9  1  0.365  0.055  0.881  1.0
  O  O10  1  0.039  0.225  0.811  1.0
  O  O11  1  0.225  0.039  0.311  1.0
  O  O12  1  0.635  0.945  0.119  1.0
  O  O13  1  0.594  0.371  0.964  1.0
  O  O14  1  0.756  0.623  0.056  1.0
  O  O15  1  0.623  0.756  0.556  1.0
  O  O16  1  0.377  0.244  0.444  1.0
  O  O17  1  0.629  0.406  0.536  1.0
  O  O18  1  0.775  0.961  0.689  1.0
  O  O19  1  0.055  0.365  0.381  1.0
  O  O20  1  0.961  0.775  0.189  1.0
  O  O21  1  0.406  0.629  0.036  1.0
  O  O22  1  0.945  0.635  0.619  1.0
  O  O23  1  0.371  0.594  0.464  1.0
[/CIF]
.
The crystal structure described by KEr(WO4)2 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 10-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. Er(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. W(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form a mixture of edge and corner-sharing WO6 octahedra. The corner-sharing octahedral tilt angles are 42°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent K(1) and two equivalent W(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to one K(1), one Er(1), and one W(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one K(1), one Er(1), and one W(1) atom. In the fourth O site, O(4) is bonded to one K(1), one Er(1), and two equivalent W(1) atoms to form a mixture of distorted edge and corner-sharing OKErW2 tetrahedra. is represented by the CIF file [CIF]
data_KEr(WO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.602
_cell_length_b   7.602
_cell_length_c   7.451
_cell_angle_alpha   62.091
_cell_angle_beta   62.091
_cell_angle_gamma   87.905
_symmetry_Int_Tables_number   1
_cell_volume   326.975
_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
  K  K0  1  0.208  0.792  0.750  1.0
  K  K1  1  0.792  0.208  0.250  1.0
  Er  Er2  1  0.224  0.776  0.250  1.0
  Er  Er3  1  0.776  0.224  0.750  1.0
  W  W4  1  0.693  0.701  0.283  1.0
  W  W5  1  0.701  0.693  0.783  1.0
  W  W6  1  0.307  0.299  0.717  1.0
  W  W7  1  0.299  0.307  0.217  1.0
  O  O8  1  0.244  0.377  0.944  1.0
  O  O9  1  0.365  0.055  0.881  1.0
  O  O10  1  0.039  0.225  0.811  1.0
  O  O11  1  0.225  0.039  0.311  1.0
  O  O12  1  0.635  0.945  0.119  1.0
  O  O13  1  0.594  0.371  0.964  1.0
  O  O14  1  0.756  0.623  0.056  1.0
  O  O15  1  0.623  0.756  0.556  1.0
  O  O16  1  0.377  0.244  0.444  1.0
  O  O17  1  0.629  0.406  0.536  1.0
  O  O18  1  0.775  0.961  0.689  1.0
  O  O19  1  0.055  0.365  0.381  1.0
  O  O20  1  0.961  0.775  0.189  1.0
  O  O21  1  0.406  0.629  0.036  1.0
  O  O22  1  0.945  0.635  0.619  1.0
  O  O23  1  0.371  0.594  0.464  1.0
[/CIF]
.