The structure described by Cs2PSe5 crystallizes in the triclinic P-1 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(2), one Se(5), two equivalent Se(1), two equivalent Se(4), and three equivalent Se(3) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to one Se(3), two equivalent Se(1), two equivalent Se(2), and four equivalent Se(5) atoms. P(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(5) atom. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(1) atom. In the second Se site, Se(2) is bonded in a 1-coordinate geometry to one Cs(1), two equivalent Cs(2), one P(1), and one Se(4) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to one Cs(2), three equivalent Cs(1), and one P(1) atom. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to two equivalent Cs(1), one Se(2), and one Se(4) atom. In the fifth Se site, Se(5) is bonded in a 6-coordinate geometry to one Cs(1), four equivalent Cs(2), and one P(1) atom. is represented by the CIF file [CIF]
data_Cs2PSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.497
_cell_length_b   7.624
_cell_length_c   10.346
_cell_angle_alpha   85.546
_cell_angle_beta   87.862
_cell_angle_gamma   85.265
_symmetry_Int_Tables_number   1
_cell_volume   587.285
_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  0.800  0.142  0.635  1.0
  Cs  Cs1  1  0.200  0.858  0.365  1.0
  Cs  Cs2  1  0.222  0.278  0.969  1.0
  Cs  Cs3  1  0.778  0.722  0.031  1.0
  P  P4  1  0.249  0.790  0.779  1.0
  P  P5  1  0.751  0.210  0.221  1.0
  Se  Se6  1  0.979  0.326  0.291  1.0
  Se  Se7  1  0.504  0.595  0.758  1.0
  Se  Se8  1  0.302  0.039  0.676  1.0
  Se  Se9  1  0.021  0.674  0.709  1.0
  Se  Se10  1  0.595  0.605  0.541  1.0
  Se  Se11  1  0.405  0.395  0.459  1.0
  Se  Se12  1  0.269  0.773  0.990  1.0
  Se  Se13  1  0.698  0.961  0.324  1.0
  Se  Se14  1  0.731  0.227  0.010  1.0
  Se  Se15  1  0.496  0.405  0.242  1.0
[/CIF]
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The structure described by Cs2PSe5 crystallizes in the triclinic P-1 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(2), one Se(5), two equivalent Se(1), two equivalent Se(4), and three equivalent Se(3) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to one Se(3), two equivalent Se(1), two equivalent Se(2), and four equivalent Se(5) atoms. P(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(5) atom. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(1) atom. In the second Se site, Se(2) is bonded in a 1-coordinate geometry to one Cs(1), two equivalent Cs(2), one P(1), and one Se(4) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to one Cs(2), three equivalent Cs(1), and one P(1) atom. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to two equivalent Cs(1), one Se(2), and one Se(4) atom. In the fifth Se site, Se(5) is bonded in a 6-coordinate geometry to one Cs(1), four equivalent Cs(2), and one P(1) atom. is represented by the CIF file [CIF]
data_Cs2PSe5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.497
_cell_length_b   7.624
_cell_length_c   10.346
_cell_angle_alpha   85.546
_cell_angle_beta   87.862
_cell_angle_gamma   85.265
_symmetry_Int_Tables_number   1
_cell_volume   587.285
_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  0.800  0.142  0.635  1.0
  Cs  Cs1  1  0.200  0.858  0.365  1.0
  Cs  Cs2  1  0.222  0.278  0.969  1.0
  Cs  Cs3  1  0.778  0.722  0.031  1.0
  P  P4  1  0.249  0.790  0.779  1.0
  P  P5  1  0.751  0.210  0.221  1.0
  Se  Se6  1  0.979  0.326  0.291  1.0
  Se  Se7  1  0.504  0.595  0.758  1.0
  Se  Se8  1  0.302  0.039  0.676  1.0
  Se  Se9  1  0.021  0.674  0.709  1.0
  Se  Se10  1  0.595  0.605  0.541  1.0
  Se  Se11  1  0.405  0.395  0.459  1.0
  Se  Se12  1  0.269  0.773  0.990  1.0
  Se  Se13  1  0.698  0.961  0.324  1.0
  Se  Se14  1  0.731  0.227  0.010  1.0
  Se  Se15  1  0.496  0.405  0.242  1.0
[/CIF]
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