The material described by Cs2Se is Cotunnite structured and crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 5-coordinate geometry to five equivalent Se(1) atoms. In the second Cs site, Cs(2) is bonded to four equivalent Se(1) atoms to form a mixture of corner and edge-sharing CsSe4 tetrahedra. Se(1) is bonded in a 9-coordinate geometry to four equivalent Cs(2) and five equivalent Cs(1) atoms. is represented by the CIF card [CIF]
data_Cs2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.547
_cell_length_b   8.975
_cell_length_c   10.879
_cell_angle_alpha   90.000
_cell_angle_beta   90.628
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   541.573
_cell_formula_units_Z   4
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  0.756  0.526  0.172  1.0
  Cs  Cs1  1  0.256  0.974  0.672  1.0
  Cs  Cs2  1  0.244  0.474  0.828  1.0
  Cs  Cs3  1  0.744  0.026  0.328  1.0
  Cs  Cs4  1  0.247  0.854  0.074  1.0
  Cs  Cs5  1  0.747  0.646  0.574  1.0
  Cs  Cs6  1  0.753  0.146  0.926  1.0
  Cs  Cs7  1  0.253  0.354  0.426  1.0
  Se  Se8  1  0.244  0.755  0.389  1.0
  Se  Se9  1  0.744  0.745  0.889  1.0
  Se  Se10  1  0.756  0.245  0.611  1.0
  Se  Se11  1  0.256  0.255  0.111  1.0
[/CIF]
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The material described by Cs2Se is Cotunnite structured and crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 5-coordinate geometry to five equivalent Se(1) atoms. In the second Cs site, Cs(2) is bonded to four equivalent Se(1) atoms to form a mixture of corner and edge-sharing CsSe4 tetrahedra. Se(1) is bonded in a 9-coordinate geometry to four equivalent Cs(2) and five equivalent Cs(1) atoms. is represented by the CIF card [CIF]
data_Cs2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.547
_cell_length_b   8.975
_cell_length_c   10.879
_cell_angle_alpha   90.000
_cell_angle_beta   90.628
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   541.573
_cell_formula_units_Z   4
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  0.756  0.526  0.172  1.0
  Cs  Cs1  1  0.256  0.974  0.672  1.0
  Cs  Cs2  1  0.244  0.474  0.828  1.0
  Cs  Cs3  1  0.744  0.026  0.328  1.0
  Cs  Cs4  1  0.247  0.854  0.074  1.0
  Cs  Cs5  1  0.747  0.646  0.574  1.0
  Cs  Cs6  1  0.753  0.146  0.926  1.0
  Cs  Cs7  1  0.253  0.354  0.426  1.0
  Se  Se8  1  0.244  0.755  0.389  1.0
  Se  Se9  1  0.744  0.745  0.889  1.0
  Se  Se10  1  0.756  0.245  0.611  1.0
  Se  Se11  1  0.256  0.255  0.111  1.0
[/CIF]
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