The crystal structure described by Cs3(SeO4)2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. In the second Cs site, Cs(2) is bonded in a 10-coordinate geometry to one O(2), three equivalent O(3), and six equivalent O(1) atoms. Se(1) is bonded in a tetrahedral geometry to one O(2), one O(3), and two equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Cs(1), three equivalent Cs(2), and one Se(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Cs(2), two equivalent Cs(1), and one Se(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cs(1), three equivalent Cs(2), and one Se(1) atom. is represented by the CIF file [CIF]
data_Cs3(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.306
_cell_length_b   6.306
_cell_length_c   8.209
_cell_angle_alpha   72.344
_cell_angle_beta   72.344
_cell_angle_gamma   60.881
_symmetry_Int_Tables_number   1
_cell_volume   266.910
_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
  Cs  Cs0  1  0.000  0.000  0.000  1.0
  Cs  Cs1  1  0.197  0.197  0.389  1.0
  Cs  Cs2  1  0.803  0.803  0.611  1.0
  Se  Se3  1  0.436  0.436  0.770  1.0
  Se  Se4  1  0.564  0.564  0.230  1.0
  O  O5  1  0.308  0.733  0.691  1.0
  O  O6  1  0.692  0.267  0.309  1.0
  O  O7  1  0.267  0.692  0.309  1.0
  O  O8  1  0.733  0.308  0.691  1.0
  O  O9  1  0.396  0.396  0.991  1.0
  O  O10  1  0.604  0.604  0.009  1.0
  O  O11  1  0.292  0.292  0.744  1.0
  O  O12  1  0.708  0.708  0.256  1.0
[/CIF]
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The crystal structure described by Cs3(SeO4)2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. In the second Cs site, Cs(2) is bonded in a 10-coordinate geometry to one O(2), three equivalent O(3), and six equivalent O(1) atoms. Se(1) is bonded in a tetrahedral geometry to one O(2), one O(3), and two equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Cs(1), three equivalent Cs(2), and one Se(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Cs(2), two equivalent Cs(1), and one Se(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cs(1), three equivalent Cs(2), and one Se(1) atom. is represented by the CIF file [CIF]
data_Cs3(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.306
_cell_length_b   6.306
_cell_length_c   8.209
_cell_angle_alpha   72.344
_cell_angle_beta   72.344
_cell_angle_gamma   60.881
_symmetry_Int_Tables_number   1
_cell_volume   266.910
_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
  Cs  Cs0  1  0.000  0.000  0.000  1.0
  Cs  Cs1  1  0.197  0.197  0.389  1.0
  Cs  Cs2  1  0.803  0.803  0.611  1.0
  Se  Se3  1  0.436  0.436  0.770  1.0
  Se  Se4  1  0.564  0.564  0.230  1.0
  O  O5  1  0.308  0.733  0.691  1.0
  O  O6  1  0.692  0.267  0.309  1.0
  O  O7  1  0.267  0.692  0.309  1.0
  O  O8  1  0.733  0.308  0.691  1.0
  O  O9  1  0.396  0.396  0.991  1.0
  O  O10  1  0.604  0.604  0.009  1.0
  O  O11  1  0.292  0.292  0.744  1.0
  O  O12  1  0.708  0.708  0.256  1.0
[/CIF]
.