The material described by Cs4P2Se9 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 8-coordinate geometry to one Se(2), one Se(3), two equivalent Se(1), and four equivalent Se(4) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), one Se(5), two equivalent Se(1), and three equivalent Se(2) atoms. P(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. There are five inequivalent Se sites. In the first Se site, Se(4) is bonded in a 6-coordinate geometry to one Cs(2), four equivalent Cs(1), and one P(1) atom. In the second Se site, Se(5) is bonded in a distorted see-saw-like geometry to two equivalent Cs(2) and two equivalent Se(3) atoms. In the third Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(1) atom. In the fourth Se site, Se(2) is bonded to one Cs(1), three equivalent Cs(2), and one P(1) atom to form a mixture of distorted edge and corner-sharing SeCs4P square pyramids. In the fifth Se site, Se(3) is bonded in a distorted single-bond geometry to one Cs(1), one Cs(2), one P(1), and one Se(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs4P2Se9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.440
_cell_length_b   7.440
_cell_length_c   19.878
_cell_angle_alpha   87.318
_cell_angle_beta   87.318
_cell_angle_gamma   93.110
_symmetry_Int_Tables_number   1
_cell_volume   1096.252
_cell_formula_units_Z   2
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  0.716  0.216  0.475  1.0
  Cs  Cs1  1  0.284  0.784  0.525  1.0
  Cs  Cs2  1  0.784  0.284  0.025  1.0
  Cs  Cs3  1  0.564  0.758  0.174  1.0
  Cs  Cs4  1  0.242  0.436  0.326  1.0
  Cs  Cs5  1  0.758  0.564  0.674  1.0
  Cs  Cs6  1  0.216  0.716  0.975  1.0
  Cs  Cs7  1  0.436  0.242  0.826  1.0
  P  P8  1  0.731  0.747  0.377  1.0
  P  P9  1  0.253  0.269  0.123  1.0
  P  P10  1  0.747  0.731  0.877  1.0
  P  P11  1  0.269  0.253  0.623  1.0
  Se  Se12  1  0.112  0.508  0.144  1.0
  Se  Se13  1  0.888  0.492  0.856  1.0
  Se  Se14  1  0.508  0.751  0.820  1.0
  Se  Se15  1  0.508  0.112  0.644  1.0
  Se  Se16  1  0.751  0.508  0.320  1.0
  Se  Se17  1  0.492  0.888  0.356  1.0
  Se  Se18  1  0.249  0.492  0.680  1.0
  Se  Se19  1  0.014  0.058  0.651  1.0
  Se  Se20  1  0.284  0.211  0.016  1.0
  Se  Se21  1  0.986  0.942  0.349  1.0
  Se  Se22  1  0.789  0.716  0.484  1.0
  Se  Se23  1  0.942  0.986  0.849  1.0
  Se  Se24  1  0.492  0.249  0.180  1.0
  Se  Se25  1  0.716  0.789  0.984  1.0
  Se  Se26  1  0.058  0.014  0.151  1.0
  Se  Se27  1  0.904  0.096  0.250  1.0
  Se  Se28  1  0.211  0.284  0.516  1.0
  Se  Se29  1  0.096  0.904  0.750  1.0
[/CIF]
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The material described by Cs4P2Se9 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 8-coordinate geometry to one Se(2), one Se(3), two equivalent Se(1), and four equivalent Se(4) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), one Se(5), two equivalent Se(1), and three equivalent Se(2) atoms. P(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. There are five inequivalent Se sites. In the first Se site, Se(4) is bonded in a 6-coordinate geometry to one Cs(2), four equivalent Cs(1), and one P(1) atom. In the second Se site, Se(5) is bonded in a distorted see-saw-like geometry to two equivalent Cs(2) and two equivalent Se(3) atoms. In the third Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(1) atom. In the fourth Se site, Se(2) is bonded to one Cs(1), three equivalent Cs(2), and one P(1) atom to form a mixture of distorted edge and corner-sharing SeCs4P square pyramids. In the fifth Se site, Se(3) is bonded in a distorted single-bond geometry to one Cs(1), one Cs(2), one P(1), and one Se(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs4P2Se9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.440
_cell_length_b   7.440
_cell_length_c   19.878
_cell_angle_alpha   87.318
_cell_angle_beta   87.318
_cell_angle_gamma   93.110
_symmetry_Int_Tables_number   1
_cell_volume   1096.252
_cell_formula_units_Z   2
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  0.716  0.216  0.475  1.0
  Cs  Cs1  1  0.284  0.784  0.525  1.0
  Cs  Cs2  1  0.784  0.284  0.025  1.0
  Cs  Cs3  1  0.564  0.758  0.174  1.0
  Cs  Cs4  1  0.242  0.436  0.326  1.0
  Cs  Cs5  1  0.758  0.564  0.674  1.0
  Cs  Cs6  1  0.216  0.716  0.975  1.0
  Cs  Cs7  1  0.436  0.242  0.826  1.0
  P  P8  1  0.731  0.747  0.377  1.0
  P  P9  1  0.253  0.269  0.123  1.0
  P  P10  1  0.747  0.731  0.877  1.0
  P  P11  1  0.269  0.253  0.623  1.0
  Se  Se12  1  0.112  0.508  0.144  1.0
  Se  Se13  1  0.888  0.492  0.856  1.0
  Se  Se14  1  0.508  0.751  0.820  1.0
  Se  Se15  1  0.508  0.112  0.644  1.0
  Se  Se16  1  0.751  0.508  0.320  1.0
  Se  Se17  1  0.492  0.888  0.356  1.0
  Se  Se18  1  0.249  0.492  0.680  1.0
  Se  Se19  1  0.014  0.058  0.651  1.0
  Se  Se20  1  0.284  0.211  0.016  1.0
  Se  Se21  1  0.986  0.942  0.349  1.0
  Se  Se22  1  0.789  0.716  0.484  1.0
  Se  Se23  1  0.942  0.986  0.849  1.0
  Se  Se24  1  0.492  0.249  0.180  1.0
  Se  Se25  1  0.716  0.789  0.984  1.0
  Se  Se26  1  0.058  0.014  0.151  1.0
  Se  Se27  1  0.904  0.096  0.250  1.0
  Se  Se28  1  0.211  0.284  0.516  1.0
  Se  Se29  1  0.096  0.904  0.750  1.0
[/CIF]
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