The structure described by K2TeSe3 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one Se(1), one Se(3), and four equivalent Se(2) atoms to form a mixture of corner and edge-sharing KSe6 octahedra. The corner-sharing octahedral tilt angles range from 10-15°. In the second K site, K(2) is bonded to one Se(2), two equivalent Se(1), and three equivalent Se(3) atoms to form a mixture of corner and edge-sharing KSe6 octahedra. The corner-sharing octahedral tilt angles range from 12-22°. Te(1) is bonded in a trigonal non-coplanar geometry to one Se(1), one Se(2), and one Se(3) atom. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to one K(1), two equivalent K(2), and one Te(1) atom. In the second Se site, Se(2) is bonded to one K(2), four equivalent K(1), and one Te(1) atom to form SeK5Te octahedra that share corners with four equivalent Se(2)K5Te octahedra, corners with two equivalent Se(3)K4Te square pyramids, edges with four equivalent Se(2)K5Te octahedra, and edges with three equivalent Se(3)K4Te square pyramids. The corner-sharing octahedral tilt angles range from 10-15°. In the third Se site, Se(3) is bonded to one K(1), three equivalent K(2), and one Te(1) atom to form SeK4Te square pyramids that share corners with two equivalent Se(2)K5Te octahedra, corners with two equivalent Se(3)K4Te square pyramids, edges with three equivalent Se(2)K5Te octahedra, and edges with two equivalent Se(3)K4Te square pyramids. The corner-sharing octahedral tilt angles range from 5-88°. is represented by the CIF card [CIF]
data_K2TeSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.634
_cell_length_b   10.273
_cell_length_c   13.241
_cell_angle_alpha   74.688
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   870.353
_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
  K  K0  1  0.252  0.492  0.625  1.0
  K  K1  1  0.752  0.508  0.875  1.0
  K  K2  1  0.748  0.508  0.375  1.0
  K  K3  1  0.248  0.492  0.125  1.0
  K  K4  1  0.756  0.840  0.546  1.0
  K  K5  1  0.256  0.160  0.954  1.0
  K  K6  1  0.244  0.160  0.454  1.0
  K  K7  1  0.744  0.840  0.046  1.0
  Te  Te8  1  0.787  0.212  0.666  1.0
  Te  Te9  1  0.713  0.212  0.166  1.0
  Te  Te10  1  0.213  0.788  0.334  1.0
  Te  Te11  1  0.287  0.788  0.834  1.0
  Se  Se12  1  0.348  0.162  0.203  1.0
  Se  Se13  1  0.755  0.464  0.634  1.0
  Se  Se14  1  0.848  0.838  0.297  1.0
  Se  Se15  1  0.652  0.838  0.797  1.0
  Se  Se16  1  0.755  0.178  0.986  1.0
  Se  Se17  1  0.255  0.536  0.866  1.0
  Se  Se18  1  0.245  0.536  0.366  1.0
  Se  Se19  1  0.745  0.464  0.134  1.0
  Se  Se20  1  0.745  0.178  0.486  1.0
  Se  Se21  1  0.255  0.822  0.514  1.0
  Se  Se22  1  0.245  0.822  0.014  1.0
  Se  Se23  1  0.152  0.162  0.703  1.0
[/CIF]
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The structure described by K2TeSe3 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one Se(1), one Se(3), and four equivalent Se(2) atoms to form a mixture of corner and edge-sharing KSe6 octahedra. The corner-sharing octahedral tilt angles range from 10-15°. In the second K site, K(2) is bonded to one Se(2), two equivalent Se(1), and three equivalent Se(3) atoms to form a mixture of corner and edge-sharing KSe6 octahedra. The corner-sharing octahedral tilt angles range from 12-22°. Te(1) is bonded in a trigonal non-coplanar geometry to one Se(1), one Se(2), and one Se(3) atom. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to one K(1), two equivalent K(2), and one Te(1) atom. In the second Se site, Se(2) is bonded to one K(2), four equivalent K(1), and one Te(1) atom to form SeK5Te octahedra that share corners with four equivalent Se(2)K5Te octahedra, corners with two equivalent Se(3)K4Te square pyramids, edges with four equivalent Se(2)K5Te octahedra, and edges with three equivalent Se(3)K4Te square pyramids. The corner-sharing octahedral tilt angles range from 10-15°. In the third Se site, Se(3) is bonded to one K(1), three equivalent K(2), and one Te(1) atom to form SeK4Te square pyramids that share corners with two equivalent Se(2)K5Te octahedra, corners with two equivalent Se(3)K4Te square pyramids, edges with three equivalent Se(2)K5Te octahedra, and edges with two equivalent Se(3)K4Te square pyramids. The corner-sharing octahedral tilt angles range from 5-88°. is represented by the CIF card [CIF]
data_K2TeSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.634
_cell_length_b   10.273
_cell_length_c   13.241
_cell_angle_alpha   74.688
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   870.353
_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
  K  K0  1  0.252  0.492  0.625  1.0
  K  K1  1  0.752  0.508  0.875  1.0
  K  K2  1  0.748  0.508  0.375  1.0
  K  K3  1  0.248  0.492  0.125  1.0
  K  K4  1  0.756  0.840  0.546  1.0
  K  K5  1  0.256  0.160  0.954  1.0
  K  K6  1  0.244  0.160  0.454  1.0
  K  K7  1  0.744  0.840  0.046  1.0
  Te  Te8  1  0.787  0.212  0.666  1.0
  Te  Te9  1  0.713  0.212  0.166  1.0
  Te  Te10  1  0.213  0.788  0.334  1.0
  Te  Te11  1  0.287  0.788  0.834  1.0
  Se  Se12  1  0.348  0.162  0.203  1.0
  Se  Se13  1  0.755  0.464  0.634  1.0
  Se  Se14  1  0.848  0.838  0.297  1.0
  Se  Se15  1  0.652  0.838  0.797  1.0
  Se  Se16  1  0.755  0.178  0.986  1.0
  Se  Se17  1  0.255  0.536  0.866  1.0
  Se  Se18  1  0.245  0.536  0.366  1.0
  Se  Se19  1  0.745  0.464  0.134  1.0
  Se  Se20  1  0.745  0.178  0.486  1.0
  Se  Se21  1  0.255  0.822  0.514  1.0
  Se  Se22  1  0.245  0.822  0.014  1.0
  Se  Se23  1  0.152  0.162  0.703  1.0
[/CIF]
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