The compound described by Cs2(PSe2)3 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 10-coordinate geometry to one Se(3), one Se(5), two equivalent Se(1), two equivalent Se(2), two equivalent Se(4), and two equivalent Se(6) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one P(1), one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(6) atoms. There are three inequivalent P sites. In the first P site, P(1) is bonded in a distorted rectangular see-saw-like geometry to one Cs(2), one P(1), one Se(3), and one Se(5) atom. In the second P site, P(2) is bonded in a 4-coordinate geometry to one P(3), one Se(1), one Se(4), and one Se(5) atom. In the third P site, P(3) is bonded in a distorted tetrahedral geometry to one P(2), one Se(2), one Se(3), and one Se(6) atom. There are six inequivalent Se sites. In the first Se site, Se(4) is bonded in a distorted single-bond geometry to one Cs(2), two equivalent Cs(1), and one P(2) atom. In the second Se site, Se(5) is bonded in an L-shaped geometry to one Cs(1), one P(1), and one P(2) atom. In the third Se site, Se(6) is bonded in a 5-coordinate geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(3) atom. In the fourth Se site, Se(1) is bonded in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(2) atom. In the fifth Se site, Se(2) is bonded in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(3) atom. In the sixth Se site, Se(3) is bonded in a distorted water-like geometry to one Cs(1), one P(1), and one P(3) atom. is represented by the CIF file [CIF]
data_Cs2(PSe2)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.761
_cell_length_b   11.023
_cell_length_c   15.490
_cell_angle_alpha   53.968
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1485.863
_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  0.999  0.756  0.255  1.0
  Cs  Cs1  1  0.001  0.244  0.745  1.0
  Cs  Cs2  1  0.499  0.244  0.245  1.0
  Cs  Cs3  1  0.501  0.756  0.755  1.0
  Cs  Cs4  1  0.999  0.344  0.179  1.0
  Cs  Cs5  1  0.001  0.656  0.821  1.0
  Cs  Cs6  1  0.499  0.656  0.321  1.0
  Cs  Cs7  1  0.501  0.344  0.679  1.0
  P  P8  1  0.951  0.996  0.439  1.0
  P  P9  1  0.049  0.004  0.561  1.0
  P  P10  1  0.451  0.004  0.061  1.0
  P  P11  1  0.549  0.996  0.939  1.0
  P  P12  1  0.684  0.853  0.444  1.0
  P  P13  1  0.316  0.147  0.556  1.0
  P  P14  1  0.184  0.147  0.056  1.0
  P  P15  1  0.816  0.853  0.944  1.0
  P  P16  1  0.700  0.641  0.055  1.0
  P  P17  1  0.300  0.359  0.945  1.0
  P  P18  1  0.200  0.359  0.445  1.0
  P  P19  1  0.800  0.641  0.555  1.0
  Se  Se20  1  0.494  0.800  0.490  1.0
  Se  Se21  1  0.506  0.200  0.510  1.0
  Se  Se22  1  0.994  0.200  0.010  1.0
  Se  Se23  1  0.006  0.800  0.990  1.0
  Se  Se24  1  0.789  0.503  0.500  1.0
  Se  Se25  1  0.211  0.497  0.500  1.0
  Se  Se26  1  0.289  0.497  0.000  1.0
  Se  Se27  1  0.711  0.503  1.000  1.0
  Se  Se28  1  0.503  0.747  0.014  1.0
  Se  Se29  1  0.497  0.253  0.986  1.0
  Se  Se30  1  0.003  0.253  0.486  1.0
  Se  Se31  1  0.997  0.747  0.514  1.0
  Se  Se32  1  0.735  0.957  0.282  1.0
  Se  Se33  1  0.265  0.043  0.718  1.0
  Se  Se34  1  0.235  0.043  0.218  1.0
  Se  Se35  1  0.765  0.957  0.782  1.0
  Se  Se36  1  0.742  0.986  0.004  1.0
  Se  Se37  1  0.258  0.014  0.996  1.0
  Se  Se38  1  0.242  0.014  0.496  1.0
  Se  Se39  1  0.758  0.986  0.504  1.0
  Se  Se40  1  0.744  0.536  0.219  1.0
  Se  Se41  1  0.256  0.464  0.781  1.0
  Se  Se42  1  0.244  0.464  0.281  1.0
  Se  Se43  1  0.756  0.536  0.719  1.0
[/CIF]
.
The compound described by Cs2(PSe2)3 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 10-coordinate geometry to one Se(3), one Se(5), two equivalent Se(1), two equivalent Se(2), two equivalent Se(4), and two equivalent Se(6) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one P(1), one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(6) atoms. There are three inequivalent P sites. In the first P site, P(1) is bonded in a distorted rectangular see-saw-like geometry to one Cs(2), one P(1), one Se(3), and one Se(5) atom. In the second P site, P(2) is bonded in a 4-coordinate geometry to one P(3), one Se(1), one Se(4), and one Se(5) atom. In the third P site, P(3) is bonded in a distorted tetrahedral geometry to one P(2), one Se(2), one Se(3), and one Se(6) atom. There are six inequivalent Se sites. In the first Se site, Se(4) is bonded in a distorted single-bond geometry to one Cs(2), two equivalent Cs(1), and one P(2) atom. In the second Se site, Se(5) is bonded in an L-shaped geometry to one Cs(1), one P(1), and one P(2) atom. In the third Se site, Se(6) is bonded in a 5-coordinate geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(3) atom. In the fourth Se site, Se(1) is bonded in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(2) atom. In the fifth Se site, Se(2) is bonded in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one P(3) atom. In the sixth Se site, Se(3) is bonded in a distorted water-like geometry to one Cs(1), one P(1), and one P(3) atom. is represented by the CIF file [CIF]
data_Cs2(PSe2)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.761
_cell_length_b   11.023
_cell_length_c   15.490
_cell_angle_alpha   53.968
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1485.863
_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  0.999  0.756  0.255  1.0
  Cs  Cs1  1  0.001  0.244  0.745  1.0
  Cs  Cs2  1  0.499  0.244  0.245  1.0
  Cs  Cs3  1  0.501  0.756  0.755  1.0
  Cs  Cs4  1  0.999  0.344  0.179  1.0
  Cs  Cs5  1  0.001  0.656  0.821  1.0
  Cs  Cs6  1  0.499  0.656  0.321  1.0
  Cs  Cs7  1  0.501  0.344  0.679  1.0
  P  P8  1  0.951  0.996  0.439  1.0
  P  P9  1  0.049  0.004  0.561  1.0
  P  P10  1  0.451  0.004  0.061  1.0
  P  P11  1  0.549  0.996  0.939  1.0
  P  P12  1  0.684  0.853  0.444  1.0
  P  P13  1  0.316  0.147  0.556  1.0
  P  P14  1  0.184  0.147  0.056  1.0
  P  P15  1  0.816  0.853  0.944  1.0
  P  P16  1  0.700  0.641  0.055  1.0
  P  P17  1  0.300  0.359  0.945  1.0
  P  P18  1  0.200  0.359  0.445  1.0
  P  P19  1  0.800  0.641  0.555  1.0
  Se  Se20  1  0.494  0.800  0.490  1.0
  Se  Se21  1  0.506  0.200  0.510  1.0
  Se  Se22  1  0.994  0.200  0.010  1.0
  Se  Se23  1  0.006  0.800  0.990  1.0
  Se  Se24  1  0.789  0.503  0.500  1.0
  Se  Se25  1  0.211  0.497  0.500  1.0
  Se  Se26  1  0.289  0.497  0.000  1.0
  Se  Se27  1  0.711  0.503  1.000  1.0
  Se  Se28  1  0.503  0.747  0.014  1.0
  Se  Se29  1  0.497  0.253  0.986  1.0
  Se  Se30  1  0.003  0.253  0.486  1.0
  Se  Se31  1  0.997  0.747  0.514  1.0
  Se  Se32  1  0.735  0.957  0.282  1.0
  Se  Se33  1  0.265  0.043  0.718  1.0
  Se  Se34  1  0.235  0.043  0.218  1.0
  Se  Se35  1  0.765  0.957  0.782  1.0
  Se  Se36  1  0.742  0.986  0.004  1.0
  Se  Se37  1  0.258  0.014  0.996  1.0
  Se  Se38  1  0.242  0.014  0.496  1.0
  Se  Se39  1  0.758  0.986  0.504  1.0
  Se  Se40  1  0.744  0.536  0.219  1.0
  Se  Se41  1  0.256  0.464  0.781  1.0
  Se  Se42  1  0.244  0.464  0.281  1.0
  Se  Se43  1  0.756  0.536  0.719  1.0
[/CIF]
.