The material described by K2WSe4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and four equivalent Se(3) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and four equivalent Se(3) atoms. W(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), and two equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent K(1), two equivalent K(2), and one W(1) atom to form distorted SeK4W trigonal bipyramids that share  a cornercorner with one Se(2)K5W octahedra, corners with four equivalent Se(1)K4W trigonal bipyramids, corners with six equivalent Se(3)K4W trigonal bipyramids, edges with five equivalent Se(2)K5W octahedra, and edges with six equivalent Se(3)K4W trigonal bipyramids. The corner-sharing octahedral tilt angles are 19°. In the second Se site, Se(2) is bonded to two equivalent K(2), three equivalent K(1), and one W(1) atom to form distorted SeK5W octahedra that share corners with four equivalent Se(2)K5W octahedra,  a cornercorner with one Se(1)K4W trigonal bipyramid, corners with ten equivalent Se(3)K4W trigonal bipyramids, edges with two equivalent Se(2)K5W octahedra, edges with five equivalent Se(1)K4W trigonal bipyramids, and edges with six equivalent Se(3)K4W trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-68°. In the third Se site, Se(3) is bonded to two equivalent K(1), two equivalent K(2), and one W(1) atom to form distorted SeK4W trigonal bipyramids that share corners with five equivalent Se(2)K5W octahedra, corners with three equivalent Se(1)K4W trigonal bipyramids, corners with six equivalent Se(3)K4W trigonal bipyramids, edges with three equivalent Se(2)K5W octahedra, edges with two equivalent Se(3)K4W trigonal bipyramids, edges with three equivalent Se(1)K4W trigonal bipyramids, and  a faceface with one Se(3)K4W trigonal bipyramid. The corner-sharing octahedral tilt angles range from 32-58°. is represented by the CIF file [CIF]
data_K2WSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.208
_cell_length_b   9.834
_cell_length_c   12.691
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   899.568
_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  0.750  0.050  0.157  1.0
  K  K1  1  0.250  0.950  0.843  1.0
  K  K2  1  0.750  0.550  0.343  1.0
  K  K3  1  0.250  0.450  0.657  1.0
  K  K4  1  0.750  0.345  0.886  1.0
  K  K5  1  0.250  0.655  0.114  1.0
  K  K6  1  0.750  0.845  0.614  1.0
  K  K7  1  0.250  0.155  0.386  1.0
  W  W8  1  0.750  0.752  0.933  1.0
  W  W9  1  0.250  0.748  0.433  1.0
  W  W10  1  0.750  0.252  0.567  1.0
  W  W11  1  0.250  0.248  0.067  1.0
  Se  Se12  1  0.250  0.279  0.885  1.0
  Se  Se13  1  0.250  0.779  0.615  1.0
  Se  Se14  1  0.750  0.221  0.385  1.0
  Se  Se15  1  0.750  0.483  0.611  1.0
  Se  Se16  1  0.750  0.983  0.889  1.0
  Se  Se17  1  0.250  0.017  0.111  1.0
  Se  Se18  1  0.492  0.147  0.637  1.0
  Se  Se19  1  0.250  0.517  0.389  1.0
  Se  Se20  1  0.008  0.647  0.863  1.0
  Se  Se21  1  0.508  0.353  0.137  1.0
  Se  Se22  1  0.008  0.147  0.637  1.0
  Se  Se23  1  0.992  0.853  0.363  1.0
  Se  Se24  1  0.992  0.353  0.137  1.0
  Se  Se25  1  0.492  0.647  0.863  1.0
  Se  Se26  1  0.508  0.853  0.363  1.0
  Se  Se27  1  0.750  0.721  0.115  1.0
[/CIF]
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The material described by K2WSe4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to two equivalent Se(1), three equivalent Se(2), and four equivalent Se(3) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), and four equivalent Se(3) atoms. W(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), and two equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent K(1), two equivalent K(2), and one W(1) atom to form distorted SeK4W trigonal bipyramids that share  a cornercorner with one Se(2)K5W octahedra, corners with four equivalent Se(1)K4W trigonal bipyramids, corners with six equivalent Se(3)K4W trigonal bipyramids, edges with five equivalent Se(2)K5W octahedra, and edges with six equivalent Se(3)K4W trigonal bipyramids. The corner-sharing octahedral tilt angles are 19°. In the second Se site, Se(2) is bonded to two equivalent K(2), three equivalent K(1), and one W(1) atom to form distorted SeK5W octahedra that share corners with four equivalent Se(2)K5W octahedra,  a cornercorner with one Se(1)K4W trigonal bipyramid, corners with ten equivalent Se(3)K4W trigonal bipyramids, edges with two equivalent Se(2)K5W octahedra, edges with five equivalent Se(1)K4W trigonal bipyramids, and edges with six equivalent Se(3)K4W trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-68°. In the third Se site, Se(3) is bonded to two equivalent K(1), two equivalent K(2), and one W(1) atom to form distorted SeK4W trigonal bipyramids that share corners with five equivalent Se(2)K5W octahedra, corners with three equivalent Se(1)K4W trigonal bipyramids, corners with six equivalent Se(3)K4W trigonal bipyramids, edges with three equivalent Se(2)K5W octahedra, edges with two equivalent Se(3)K4W trigonal bipyramids, edges with three equivalent Se(1)K4W trigonal bipyramids, and  a faceface with one Se(3)K4W trigonal bipyramid. The corner-sharing octahedral tilt angles range from 32-58°. is represented by the CIF file [CIF]
data_K2WSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.208
_cell_length_b   9.834
_cell_length_c   12.691
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   899.568
_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  0.750  0.050  0.157  1.0
  K  K1  1  0.250  0.950  0.843  1.0
  K  K2  1  0.750  0.550  0.343  1.0
  K  K3  1  0.250  0.450  0.657  1.0
  K  K4  1  0.750  0.345  0.886  1.0
  K  K5  1  0.250  0.655  0.114  1.0
  K  K6  1  0.750  0.845  0.614  1.0
  K  K7  1  0.250  0.155  0.386  1.0
  W  W8  1  0.750  0.752  0.933  1.0
  W  W9  1  0.250  0.748  0.433  1.0
  W  W10  1  0.750  0.252  0.567  1.0
  W  W11  1  0.250  0.248  0.067  1.0
  Se  Se12  1  0.250  0.279  0.885  1.0
  Se  Se13  1  0.250  0.779  0.615  1.0
  Se  Se14  1  0.750  0.221  0.385  1.0
  Se  Se15  1  0.750  0.483  0.611  1.0
  Se  Se16  1  0.750  0.983  0.889  1.0
  Se  Se17  1  0.250  0.017  0.111  1.0
  Se  Se18  1  0.492  0.147  0.637  1.0
  Se  Se19  1  0.250  0.517  0.389  1.0
  Se  Se20  1  0.008  0.647  0.863  1.0
  Se  Se21  1  0.508  0.353  0.137  1.0
  Se  Se22  1  0.008  0.147  0.637  1.0
  Se  Se23  1  0.992  0.853  0.363  1.0
  Se  Se24  1  0.992  0.353  0.137  1.0
  Se  Se25  1  0.492  0.647  0.863  1.0
  Se  Se26  1  0.508  0.853  0.363  1.0
  Se  Se27  1  0.750  0.721  0.115  1.0
[/CIF]
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