The crystal structure described by Er2(SeO4)3 crystallizes in the monoclinic C2 space group. Er(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(5), two equivalent O(2), and two equivalent O(4) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one O(1), one O(4), and one O(6) atom. In the second Se site, Se(2) is bonded in a tetrahedral geometry to two equivalent O(3) and two equivalent O(5) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Er(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to two equivalent Er(1) and one O(4) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Er(1) and one Se(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Er(1), one Se(1), and one O(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Er(1) and one Se(2) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one Se(1) atom. is represented by the CIF card [CIF]
data_Er2(SeO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.291
_cell_length_b   7.291
_cell_length_c   6.401
_cell_angle_alpha   74.743
_cell_angle_beta   74.743
_cell_angle_gamma   60.752
_symmetry_Int_Tables_number   1
_cell_volume   282.770
_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  0.271  0.136  0.159  1.0
  Er  Er1  1  0.864  0.729  0.841  1.0
  Se  Se2  1  0.490  0.218  0.511  1.0
  Se  Se3  1  0.782  0.510  0.489  1.0
  Se  Se4  1  0.349  0.651  0.000  1.0
  O  O5  1  0.365  0.086  0.472  1.0
  O  O6  1  0.914  0.635  0.528  1.0
  O  O7  1  0.611  0.004  0.001  1.0
  O  O8  1  0.996  0.389  0.999  1.0
  O  O9  1  0.263  0.822  0.177  1.0
  O  O10  1  0.178  0.737  0.823  1.0
  O  O11  1  0.963  0.513  0.171  1.0
  O  O12  1  0.487  0.037  0.829  1.0
  O  O13  1  0.380  0.410  0.133  1.0
  O  O14  1  0.590  0.620  0.867  1.0
  O  O15  1  0.740  0.092  0.406  1.0
  O  O16  1  0.908  0.260  0.594  1.0
[/CIF]
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The crystal structure described by Er2(SeO4)3 crystallizes in the monoclinic C2 space group. Er(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(5), two equivalent O(2), and two equivalent O(4) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one O(1), one O(4), and one O(6) atom. In the second Se site, Se(2) is bonded in a tetrahedral geometry to two equivalent O(3) and two equivalent O(5) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Er(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to two equivalent Er(1) and one O(4) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Er(1) and one Se(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Er(1), one Se(1), and one O(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Er(1) and one Se(2) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one Se(1) atom. is represented by the CIF card [CIF]
data_Er2(SeO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.291
_cell_length_b   7.291
_cell_length_c   6.401
_cell_angle_alpha   74.743
_cell_angle_beta   74.743
_cell_angle_gamma   60.752
_symmetry_Int_Tables_number   1
_cell_volume   282.770
_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  0.271  0.136  0.159  1.0
  Er  Er1  1  0.864  0.729  0.841  1.0
  Se  Se2  1  0.490  0.218  0.511  1.0
  Se  Se3  1  0.782  0.510  0.489  1.0
  Se  Se4  1  0.349  0.651  0.000  1.0
  O  O5  1  0.365  0.086  0.472  1.0
  O  O6  1  0.914  0.635  0.528  1.0
  O  O7  1  0.611  0.004  0.001  1.0
  O  O8  1  0.996  0.389  0.999  1.0
  O  O9  1  0.263  0.822  0.177  1.0
  O  O10  1  0.178  0.737  0.823  1.0
  O  O11  1  0.963  0.513  0.171  1.0
  O  O12  1  0.487  0.037  0.829  1.0
  O  O13  1  0.380  0.410  0.133  1.0
  O  O14  1  0.590  0.620  0.867  1.0
  O  O15  1  0.740  0.092  0.406  1.0
  O  O16  1  0.908  0.260  0.594  1.0
[/CIF]
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