The material structure described by Cs2Se is Cotunnite structured and crystallizes in the orthorhombic Pnma 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 edge and corner-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 file [CIF]
data_Cs2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.543
_cell_length_b   8.964
_cell_length_c   10.890
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   541.179
_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  0.750  0.474  0.672  1.0
  Cs  Cs1  1  0.750  0.974  0.828  1.0
  Cs  Cs2  1  0.250  0.526  0.328  1.0
  Cs  Cs3  1  0.250  0.026  0.172  1.0
  Cs  Cs4  1  0.750  0.355  0.074  1.0
  Cs  Cs5  1  0.750  0.855  0.426  1.0
  Cs  Cs6  1  0.250  0.645  0.926  1.0
  Cs  Cs7  1  0.250  0.145  0.574  1.0
  Se  Se8  1  0.750  0.255  0.388  1.0
  Se  Se9  1  0.750  0.755  0.112  1.0
  Se  Se10  1  0.250  0.745  0.612  1.0
  Se  Se11  1  0.250  0.245  0.888  1.0
[/CIF]
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The material structure described by Cs2Se is Cotunnite structured and crystallizes in the orthorhombic Pnma 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 edge and corner-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 file [CIF]
data_Cs2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.543
_cell_length_b   8.964
_cell_length_c   10.890
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   541.179
_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  0.750  0.474  0.672  1.0
  Cs  Cs1  1  0.750  0.974  0.828  1.0
  Cs  Cs2  1  0.250  0.526  0.328  1.0
  Cs  Cs3  1  0.250  0.026  0.172  1.0
  Cs  Cs4  1  0.750  0.355  0.074  1.0
  Cs  Cs5  1  0.750  0.855  0.426  1.0
  Cs  Cs6  1  0.250  0.645  0.926  1.0
  Cs  Cs7  1  0.250  0.145  0.574  1.0
  Se  Se8  1  0.750  0.255  0.388  1.0
  Se  Se9  1  0.750  0.755  0.112  1.0
  Se  Se10  1  0.250  0.745  0.612  1.0
  Se  Se11  1  0.250  0.245  0.888  1.0
[/CIF]
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