The structure described by K2Sn2Se5 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and three equivalent Se(3) atoms. Sn(1) is bonded to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing SnSe5 trigonal bipyramids. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to four equivalent K(1) and two equivalent Sn(1) atoms. In the second Se site, Se(2) is bonded to three equivalent K(1) and two equivalent Sn(1) atoms to form a mixture of corner and edge-sharing SeK3Sn2 square pyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to three equivalent K(1) and two equivalent Sn(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2Sn2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.143
_cell_length_b   7.143
_cell_length_c   12.096
_cell_angle_alpha   75.069
_cell_angle_beta   75.069
_cell_angle_gamma   70.454
_symmetry_Int_Tables_number   1
_cell_volume   551.969
_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
  K  K0  1  0.563  0.898  0.681  1.0
  K  K1  1  0.102  0.437  0.819  1.0
  K  K2  1  0.437  0.102  0.319  1.0
  K  K3  1  0.898  0.563  0.181  1.0
  Sn  Sn4  1  0.752  0.057  0.942  1.0
  Sn  Sn5  1  0.057  0.752  0.442  1.0
  Sn  Sn6  1  0.248  0.943  0.058  1.0
  Sn  Sn7  1  0.943  0.248  0.558  1.0
  Se  Se8  1  0.320  0.680  0.250  1.0
  Se  Se9  1  0.680  0.320  0.750  1.0
  Se  Se10  1  0.741  0.648  0.462  1.0
  Se  Se11  1  0.882  0.155  0.380  1.0
  Se  Se12  1  0.352  0.259  0.038  1.0
  Se  Se13  1  0.259  0.352  0.538  1.0
  Se  Se14  1  0.648  0.741  0.962  1.0
  Se  Se15  1  0.118  0.845  0.620  1.0
  Se  Se16  1  0.155  0.882  0.880  1.0
  Se  Se17  1  0.845  0.118  0.120  1.0
[/CIF]
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The structure described by K2Sn2Se5 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and three equivalent Se(3) atoms. Sn(1) is bonded to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form a mixture of corner and edge-sharing SnSe5 trigonal bipyramids. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to four equivalent K(1) and two equivalent Sn(1) atoms. In the second Se site, Se(2) is bonded to three equivalent K(1) and two equivalent Sn(1) atoms to form a mixture of corner and edge-sharing SeK3Sn2 square pyramids. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to three equivalent K(1) and two equivalent Sn(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2Sn2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.143
_cell_length_b   7.143
_cell_length_c   12.096
_cell_angle_alpha   75.069
_cell_angle_beta   75.069
_cell_angle_gamma   70.454
_symmetry_Int_Tables_number   1
_cell_volume   551.969
_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
  K  K0  1  0.563  0.898  0.681  1.0
  K  K1  1  0.102  0.437  0.819  1.0
  K  K2  1  0.437  0.102  0.319  1.0
  K  K3  1  0.898  0.563  0.181  1.0
  Sn  Sn4  1  0.752  0.057  0.942  1.0
  Sn  Sn5  1  0.057  0.752  0.442  1.0
  Sn  Sn6  1  0.248  0.943  0.058  1.0
  Sn  Sn7  1  0.943  0.248  0.558  1.0
  Se  Se8  1  0.320  0.680  0.250  1.0
  Se  Se9  1  0.680  0.320  0.750  1.0
  Se  Se10  1  0.741  0.648  0.462  1.0
  Se  Se11  1  0.882  0.155  0.380  1.0
  Se  Se12  1  0.352  0.259  0.038  1.0
  Se  Se13  1  0.259  0.352  0.538  1.0
  Se  Se14  1  0.648  0.741  0.962  1.0
  Se  Se15  1  0.118  0.845  0.620  1.0
  Se  Se16  1  0.155  0.882  0.880  1.0
  Se  Se17  1  0.845  0.118  0.120  1.0
[/CIF]
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