The structure described by K4SnSe4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent K sites. In the first K site, K(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form distorted KSe6 octahedra that share corners with two equivalent Sn(1)K2Se4 tetrahedra, edges with two equivalent K(1)Se6 octahedra, and edges with two equivalent Sn(1)K2Se4 tetrahedra. In the second K site, K(2) is bonded in a 6-coordinate geometry to one Se(1), one Se(3), and four equivalent Se(2) atoms. In the third K site, K(3) is bonded in a 7-coordinate geometry to one Sn(1), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. Sn(1) is bonded to two equivalent K(3), one Se(1), one Se(3), and two equivalent Se(2) atoms to form SnK2Se4 tetrahedra that share corners with two equivalent K(1)Se6 octahedra, corners with four equivalent Se(2)K5Sn octahedra, and edges with two equivalent K(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 43-138°. There are three inequivalent Se sites. In the first Se site, Se(3) is bonded in a 8-coordinate geometry to one K(2), two equivalent K(1), four equivalent K(3), and one Sn(1) atom. In the second Se site, Se(1) is bonded in a 8-coordinate geometry to one K(2), two equivalent K(1), four equivalent K(3), and one Sn(1) atom. In the third Se site, Se(2) is bonded to one K(1), two equivalent K(2), two equivalent K(3), and one Sn(1) atom to form distorted SeK5Sn octahedra that share corners with six equivalent Se(2)K5Sn octahedra, corners with two equivalent Sn(1)K2Se4 tetrahedra, and edges with two equivalent Se(2)K5Sn octahedra. The corner-sharing octahedral tilt angles range from 0-46°. is represented by the Crystallographic Information File (CIF) [CIF]
data_K4SnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.359
_cell_length_b   10.302
_cell_length_c   14.774
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1272.205
_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  0.000  0.000  0.000  1.0
  K  K1  1  0.500  0.000  0.500  1.0
  K  K2  1  0.000  0.500  0.000  1.0
  K  K3  1  0.500  0.500  0.500  1.0
  K  K4  1  0.987  0.750  0.423  1.0
  K  K5  1  0.487  0.250  0.077  1.0
  K  K6  1  0.013  0.250  0.577  1.0
  K  K7  1  0.513  0.750  0.923  1.0
  K  K8  1  0.843  0.049  0.272  1.0
  K  K9  1  0.343  0.951  0.228  1.0
  K  K10  1  0.157  0.549  0.728  1.0
  K  K11  1  0.657  0.451  0.772  1.0
  K  K12  1  0.157  0.951  0.728  1.0
  K  K13  1  0.657  0.049  0.772  1.0
  K  K14  1  0.843  0.451  0.272  1.0
  K  K15  1  0.343  0.549  0.228  1.0
  Sn  Sn16  1  0.761  0.750  0.666  1.0
  Sn  Sn17  1  0.239  0.250  0.334  1.0
  Sn  Sn18  1  0.739  0.750  0.166  1.0
  Sn  Sn19  1  0.261  0.250  0.834  1.0
  Se  Se20  1  0.957  0.250  0.826  1.0
  Se  Se21  1  0.543  0.250  0.326  1.0
  Se  Se22  1  0.457  0.750  0.674  1.0
  Se  Se23  1  0.043  0.750  0.174  1.0
  Se  Se24  1  0.644  0.549  0.085  1.0
  Se  Se25  1  0.144  0.451  0.415  1.0
  Se  Se26  1  0.356  0.049  0.915  1.0
  Se  Se27  1  0.856  0.951  0.585  1.0
  Se  Se28  1  0.356  0.451  0.915  1.0
  Se  Se29  1  0.856  0.549  0.585  1.0
  Se  Se30  1  0.644  0.951  0.085  1.0
  Se  Se31  1  0.144  0.049  0.415  1.0
  Se  Se32  1  0.622  0.750  0.326  1.0
  Se  Se33  1  0.122  0.250  0.174  1.0
  Se  Se34  1  0.378  0.250  0.674  1.0
  Se  Se35  1  0.878  0.750  0.826  1.0
[/CIF]
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The structure described by K4SnSe4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent K sites. In the first K site, K(1) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form distorted KSe6 octahedra that share corners with two equivalent Sn(1)K2Se4 tetrahedra, edges with two equivalent K(1)Se6 octahedra, and edges with two equivalent Sn(1)K2Se4 tetrahedra. In the second K site, K(2) is bonded in a 6-coordinate geometry to one Se(1), one Se(3), and four equivalent Se(2) atoms. In the third K site, K(3) is bonded in a 7-coordinate geometry to one Sn(1), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. Sn(1) is bonded to two equivalent K(3), one Se(1), one Se(3), and two equivalent Se(2) atoms to form SnK2Se4 tetrahedra that share corners with two equivalent K(1)Se6 octahedra, corners with four equivalent Se(2)K5Sn octahedra, and edges with two equivalent K(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 43-138°. There are three inequivalent Se sites. In the first Se site, Se(3) is bonded in a 8-coordinate geometry to one K(2), two equivalent K(1), four equivalent K(3), and one Sn(1) atom. In the second Se site, Se(1) is bonded in a 8-coordinate geometry to one K(2), two equivalent K(1), four equivalent K(3), and one Sn(1) atom. In the third Se site, Se(2) is bonded to one K(1), two equivalent K(2), two equivalent K(3), and one Sn(1) atom to form distorted SeK5Sn octahedra that share corners with six equivalent Se(2)K5Sn octahedra, corners with two equivalent Sn(1)K2Se4 tetrahedra, and edges with two equivalent Se(2)K5Sn octahedra. The corner-sharing octahedral tilt angles range from 0-46°. is represented by the Crystallographic Information File (CIF) [CIF]
data_K4SnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.359
_cell_length_b   10.302
_cell_length_c   14.774
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1272.205
_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  0.000  0.000  0.000  1.0
  K  K1  1  0.500  0.000  0.500  1.0
  K  K2  1  0.000  0.500  0.000  1.0
  K  K3  1  0.500  0.500  0.500  1.0
  K  K4  1  0.987  0.750  0.423  1.0
  K  K5  1  0.487  0.250  0.077  1.0
  K  K6  1  0.013  0.250  0.577  1.0
  K  K7  1  0.513  0.750  0.923  1.0
  K  K8  1  0.843  0.049  0.272  1.0
  K  K9  1  0.343  0.951  0.228  1.0
  K  K10  1  0.157  0.549  0.728  1.0
  K  K11  1  0.657  0.451  0.772  1.0
  K  K12  1  0.157  0.951  0.728  1.0
  K  K13  1  0.657  0.049  0.772  1.0
  K  K14  1  0.843  0.451  0.272  1.0
  K  K15  1  0.343  0.549  0.228  1.0
  Sn  Sn16  1  0.761  0.750  0.666  1.0
  Sn  Sn17  1  0.239  0.250  0.334  1.0
  Sn  Sn18  1  0.739  0.750  0.166  1.0
  Sn  Sn19  1  0.261  0.250  0.834  1.0
  Se  Se20  1  0.957  0.250  0.826  1.0
  Se  Se21  1  0.543  0.250  0.326  1.0
  Se  Se22  1  0.457  0.750  0.674  1.0
  Se  Se23  1  0.043  0.750  0.174  1.0
  Se  Se24  1  0.644  0.549  0.085  1.0
  Se  Se25  1  0.144  0.451  0.415  1.0
  Se  Se26  1  0.356  0.049  0.915  1.0
  Se  Se27  1  0.856  0.951  0.585  1.0
  Se  Se28  1  0.356  0.451  0.915  1.0
  Se  Se29  1  0.856  0.549  0.585  1.0
  Se  Se30  1  0.644  0.951  0.085  1.0
  Se  Se31  1  0.144  0.049  0.415  1.0
  Se  Se32  1  0.622  0.750  0.326  1.0
  Se  Se33  1  0.122  0.250  0.174  1.0
  Se  Se34  1  0.378  0.250  0.674  1.0
  Se  Se35  1  0.878  0.750  0.826  1.0
[/CIF]
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