The compound described by Cs2Si2Se5 crystallizes in the monoclinic C2/c space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to one Se(5), two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Se(1), one Se(3), one Se(4), two equivalent Se(6), and three equivalent Se(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one Se(2), one Se(3), one Se(4), and one Se(6) atom to form corner-sharing SiSe4 tetrahedra. In the second Si site, Si(2) is bonded to one Se(1), one Se(3), one Se(4), and one Se(5) atom to form corner-sharing SiSe4 tetrahedra. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one Cs(2), two equivalent Cs(1), and one Si(2) atom. In the second Se site, Se(2) is bonded in a 1-coordinate geometry to two equivalent Cs(1), three equivalent Cs(2), and one Si(1) atom. In the third Se site, Se(3) is bonded in a distorted water-like geometry to one Cs(2), two equivalent Cs(1), one Si(1), and one Si(2) atom. In the fourth Se site, Se(4) is bonded in a 5-coordinate geometry to one Cs(2), two equivalent Cs(1), one Si(1), and one Si(2) atom. In the fifth Se site, Se(5) is bonded in a distorted water-like geometry to two equivalent Cs(1) and two equivalent Si(2) atoms. In the sixth Se site, Se(6) is bonded in a distorted water-like geometry to four equivalent Cs(2) and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Cs2Si2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.696
_cell_length_b   11.696
_cell_length_c   9.813
_cell_angle_alpha   80.820
_cell_angle_beta   80.820
_cell_angle_gamma   90.125
_symmetry_Int_Tables_number   1
_cell_volume   1307.822
_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  0.709  0.981  0.367  1.0
  Cs  Cs1  1  0.019  0.291  0.133  1.0
  Cs  Cs2  1  0.291  0.019  0.633  1.0
  Cs  Cs3  1  0.981  0.709  0.867  1.0
  Cs  Cs4  1  0.552  0.708  0.873  1.0
  Cs  Cs5  1  0.292  0.448  0.627  1.0
  Cs  Cs6  1  0.448  0.292  0.127  1.0
  Cs  Cs7  1  0.708  0.552  0.373  1.0
  Si  Si8  1  0.359  0.769  0.383  1.0
  Si  Si9  1  0.231  0.641  0.117  1.0
  Si  Si10  1  0.641  0.231  0.617  1.0
  Si  Si11  1  0.769  0.359  0.883  1.0
  Si  Si12  1  0.767  0.037  0.888  1.0
  Si  Si13  1  0.963  0.233  0.612  1.0
  Si  Si14  1  0.233  0.963  0.112  1.0
  Si  Si15  1  0.037  0.767  0.388  1.0
  Se  Se16  1  0.747  0.871  0.028  1.0
  Se  Se17  1  0.129  0.253  0.472  1.0
  Se  Se18  1  0.253  0.129  0.972  1.0
  Se  Se19  1  0.871  0.747  0.528  1.0
  Se  Se20  1  0.489  0.748  0.522  1.0
  Se  Se21  1  0.252  0.511  0.978  1.0
  Se  Se22  1  0.511  0.252  0.478  1.0
  Se  Se23  1  0.748  0.489  0.022  1.0
  Se  Se24  1  0.619  0.053  0.755  1.0
  Se  Se25  1  0.947  0.381  0.745  1.0
  Se  Se26  1  0.381  0.947  0.245  1.0
  Se  Se27  1  0.053  0.619  0.255  1.0
  Se  Se28  1  0.747  0.181  0.026  1.0
  Se  Se29  1  0.819  0.253  0.474  1.0
  Se  Se30  1  0.253  0.819  0.974  1.0
  Se  Se31  1  0.181  0.747  0.526  1.0
  Se  Se32  1  0.946  0.054  0.750  1.0
  Se  Se33  1  0.054  0.946  0.250  1.0
  Se  Se34  1  0.379  0.621  0.250  1.0
  Se  Se35  1  0.621  0.379  0.750  1.0
[/CIF]
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The compound described by Cs2Si2Se5 crystallizes in the monoclinic C2/c space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to one Se(5), two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Se(1), one Se(3), one Se(4), two equivalent Se(6), and three equivalent Se(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one Se(2), one Se(3), one Se(4), and one Se(6) atom to form corner-sharing SiSe4 tetrahedra. In the second Si site, Si(2) is bonded to one Se(1), one Se(3), one Se(4), and one Se(5) atom to form corner-sharing SiSe4 tetrahedra. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one Cs(2), two equivalent Cs(1), and one Si(2) atom. In the second Se site, Se(2) is bonded in a 1-coordinate geometry to two equivalent Cs(1), three equivalent Cs(2), and one Si(1) atom. In the third Se site, Se(3) is bonded in a distorted water-like geometry to one Cs(2), two equivalent Cs(1), one Si(1), and one Si(2) atom. In the fourth Se site, Se(4) is bonded in a 5-coordinate geometry to one Cs(2), two equivalent Cs(1), one Si(1), and one Si(2) atom. In the fifth Se site, Se(5) is bonded in a distorted water-like geometry to two equivalent Cs(1) and two equivalent Si(2) atoms. In the sixth Se site, Se(6) is bonded in a distorted water-like geometry to four equivalent Cs(2) and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Cs2Si2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.696
_cell_length_b   11.696
_cell_length_c   9.813
_cell_angle_alpha   80.820
_cell_angle_beta   80.820
_cell_angle_gamma   90.125
_symmetry_Int_Tables_number   1
_cell_volume   1307.822
_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  0.709  0.981  0.367  1.0
  Cs  Cs1  1  0.019  0.291  0.133  1.0
  Cs  Cs2  1  0.291  0.019  0.633  1.0
  Cs  Cs3  1  0.981  0.709  0.867  1.0
  Cs  Cs4  1  0.552  0.708  0.873  1.0
  Cs  Cs5  1  0.292  0.448  0.627  1.0
  Cs  Cs6  1  0.448  0.292  0.127  1.0
  Cs  Cs7  1  0.708  0.552  0.373  1.0
  Si  Si8  1  0.359  0.769  0.383  1.0
  Si  Si9  1  0.231  0.641  0.117  1.0
  Si  Si10  1  0.641  0.231  0.617  1.0
  Si  Si11  1  0.769  0.359  0.883  1.0
  Si  Si12  1  0.767  0.037  0.888  1.0
  Si  Si13  1  0.963  0.233  0.612  1.0
  Si  Si14  1  0.233  0.963  0.112  1.0
  Si  Si15  1  0.037  0.767  0.388  1.0
  Se  Se16  1  0.747  0.871  0.028  1.0
  Se  Se17  1  0.129  0.253  0.472  1.0
  Se  Se18  1  0.253  0.129  0.972  1.0
  Se  Se19  1  0.871  0.747  0.528  1.0
  Se  Se20  1  0.489  0.748  0.522  1.0
  Se  Se21  1  0.252  0.511  0.978  1.0
  Se  Se22  1  0.511  0.252  0.478  1.0
  Se  Se23  1  0.748  0.489  0.022  1.0
  Se  Se24  1  0.619  0.053  0.755  1.0
  Se  Se25  1  0.947  0.381  0.745  1.0
  Se  Se26  1  0.381  0.947  0.245  1.0
  Se  Se27  1  0.053  0.619  0.255  1.0
  Se  Se28  1  0.747  0.181  0.026  1.0
  Se  Se29  1  0.819  0.253  0.474  1.0
  Se  Se30  1  0.253  0.819  0.974  1.0
  Se  Se31  1  0.181  0.747  0.526  1.0
  Se  Se32  1  0.946  0.054  0.750  1.0
  Se  Se33  1  0.054  0.946  0.250  1.0
  Se  Se34  1  0.379  0.621  0.250  1.0
  Se  Se35  1  0.621  0.379  0.750  1.0
[/CIF]
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