The crystal structure described by Cs2SnAs2Se9 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 12-coordinate geometry to one As(1), one Se(1), one Se(2), one Se(5), one Se(6), one Se(7), two equivalent Se(3), two equivalent Se(8), and two equivalent Se(9) atoms. In the second Cs site, Cs(2) is bonded in a 11-coordinate geometry to one Se(1), one Se(3), one Se(9), two equivalent Se(2), two equivalent Se(4), two equivalent Se(5), and two equivalent Se(7) atoms. Sn(1) is bonded in an octahedral geometry to one Se(1), one Se(2), one Se(3), one Se(4), one Se(7), and one Se(8) atom. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 3-coordinate geometry to one Cs(1), one Se(2), one Se(4), and one Se(5) atom. In the second As site, As(2) is bonded in a trigonal non-coplanar geometry to one Se(6), one Se(8), and one Se(9) atom. There are nine inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal pyramidal geometry to one Cs(1), one Cs(2), one Sn(1), and one Se(6) atom. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Cs(1), two equivalent Cs(2), one Sn(1), and one As(1) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to one Cs(2), two equivalent Cs(1), one Sn(1), and one Se(9) atom. In the fourth Se site, Se(4) is bonded in a distorted L-shaped geometry to two equivalent Cs(2), one Sn(1), and one As(1) atom. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one Cs(1), two equivalent Cs(2), one As(1), and one Se(7) atom. In the sixth Se site, Se(6) is bonded in a 3-coordinate geometry to one Cs(1), one As(2), and one Se(1) atom. In the seventh Se site, Se(7) is bonded in a 5-coordinate geometry to one Cs(1), two equivalent Cs(2), one Sn(1), and one Se(5) atom. In the eighth Se site, Se(8) is bonded in a distorted water-like geometry to two equivalent Cs(1), one Sn(1), and one As(2) atom. In the ninth Se site, Se(9) is bonded in a 1-coordinate geometry to one Cs(2), two equivalent Cs(1), one As(2), and one Se(3) atom. is represented by the CIF card [CIF]
data_Cs2SnAs2Se9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   18.197
_cell_length_b   7.429
_cell_length_c   8.000
_cell_angle_alpha   64.785
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   978.397
_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  0.063  0.692  0.242  1.0
  Cs  Cs1  1  0.792  0.085  0.483  1.0
  Cs  Cs2  1  0.563  0.308  0.758  1.0
  Cs  Cs3  1  0.292  0.915  0.517  1.0
  Sn  Sn4  1  0.668  0.677  0.118  1.0
  Sn  Sn5  1  0.168  0.323  0.882  1.0
  As  As6  1  0.355  0.191  0.936  1.0
  As  As7  1  0.954  0.362  0.841  1.0
  As  As8  1  0.454  0.638  0.159  1.0
  As  As9  1  0.855  0.809  0.064  1.0
  Se  Se10  1  0.118  0.701  0.792  1.0
  Se  Se11  1  0.753  0.027  0.006  1.0
  Se  Se12  1  0.106  0.187  0.228  1.0
  Se  Se13  1  0.293  0.433  0.010  1.0
  Se  Se14  1  0.851  0.625  0.412  1.0
  Se  Se15  1  0.995  0.708  0.690  1.0
  Se  Se16  1  0.224  0.397  0.536  1.0
  Se  Se17  1  0.351  0.375  0.588  1.0
  Se  Se18  1  0.793  0.567  0.990  1.0
  Se  Se19  1  0.048  0.199  0.756  1.0
  Se  Se20  1  0.253  0.973  0.994  1.0
  Se  Se21  1  0.479  0.744  0.827  1.0
  Se  Se22  1  0.495  0.292  0.310  1.0
  Se  Se23  1  0.724  0.603  0.464  1.0
  Se  Se24  1  0.606  0.813  0.772  1.0
  Se  Se25  1  0.548  0.801  0.244  1.0
  Se  Se26  1  0.618  0.299  0.208  1.0
  Se  Se27  1  0.979  0.256  0.173  1.0
[/CIF]
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The crystal structure described by Cs2SnAs2Se9 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 12-coordinate geometry to one As(1), one Se(1), one Se(2), one Se(5), one Se(6), one Se(7), two equivalent Se(3), two equivalent Se(8), and two equivalent Se(9) atoms. In the second Cs site, Cs(2) is bonded in a 11-coordinate geometry to one Se(1), one Se(3), one Se(9), two equivalent Se(2), two equivalent Se(4), two equivalent Se(5), and two equivalent Se(7) atoms. Sn(1) is bonded in an octahedral geometry to one Se(1), one Se(2), one Se(3), one Se(4), one Se(7), and one Se(8) atom. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 3-coordinate geometry to one Cs(1), one Se(2), one Se(4), and one Se(5) atom. In the second As site, As(2) is bonded in a trigonal non-coplanar geometry to one Se(6), one Se(8), and one Se(9) atom. There are nine inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal pyramidal geometry to one Cs(1), one Cs(2), one Sn(1), and one Se(6) atom. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Cs(1), two equivalent Cs(2), one Sn(1), and one As(1) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to one Cs(2), two equivalent Cs(1), one Sn(1), and one Se(9) atom. In the fourth Se site, Se(4) is bonded in a distorted L-shaped geometry to two equivalent Cs(2), one Sn(1), and one As(1) atom. In the fifth Se site, Se(5) is bonded in a 5-coordinate geometry to one Cs(1), two equivalent Cs(2), one As(1), and one Se(7) atom. In the sixth Se site, Se(6) is bonded in a 3-coordinate geometry to one Cs(1), one As(2), and one Se(1) atom. In the seventh Se site, Se(7) is bonded in a 5-coordinate geometry to one Cs(1), two equivalent Cs(2), one Sn(1), and one Se(5) atom. In the eighth Se site, Se(8) is bonded in a distorted water-like geometry to two equivalent Cs(1), one Sn(1), and one As(2) atom. In the ninth Se site, Se(9) is bonded in a 1-coordinate geometry to one Cs(2), two equivalent Cs(1), one As(2), and one Se(3) atom. is represented by the CIF card [CIF]
data_Cs2SnAs2Se9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   18.197
_cell_length_b   7.429
_cell_length_c   8.000
_cell_angle_alpha   64.785
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   978.397
_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  0.063  0.692  0.242  1.0
  Cs  Cs1  1  0.792  0.085  0.483  1.0
  Cs  Cs2  1  0.563  0.308  0.758  1.0
  Cs  Cs3  1  0.292  0.915  0.517  1.0
  Sn  Sn4  1  0.668  0.677  0.118  1.0
  Sn  Sn5  1  0.168  0.323  0.882  1.0
  As  As6  1  0.355  0.191  0.936  1.0
  As  As7  1  0.954  0.362  0.841  1.0
  As  As8  1  0.454  0.638  0.159  1.0
  As  As9  1  0.855  0.809  0.064  1.0
  Se  Se10  1  0.118  0.701  0.792  1.0
  Se  Se11  1  0.753  0.027  0.006  1.0
  Se  Se12  1  0.106  0.187  0.228  1.0
  Se  Se13  1  0.293  0.433  0.010  1.0
  Se  Se14  1  0.851  0.625  0.412  1.0
  Se  Se15  1  0.995  0.708  0.690  1.0
  Se  Se16  1  0.224  0.397  0.536  1.0
  Se  Se17  1  0.351  0.375  0.588  1.0
  Se  Se18  1  0.793  0.567  0.990  1.0
  Se  Se19  1  0.048  0.199  0.756  1.0
  Se  Se20  1  0.253  0.973  0.994  1.0
  Se  Se21  1  0.479  0.744  0.827  1.0
  Se  Se22  1  0.495  0.292  0.310  1.0
  Se  Se23  1  0.724  0.603  0.464  1.0
  Se  Se24  1  0.606  0.813  0.772  1.0
  Se  Se25  1  0.548  0.801  0.244  1.0
  Se  Se26  1  0.618  0.299  0.208  1.0
  Se  Se27  1  0.979  0.256  0.173  1.0
[/CIF]
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