The material described by K3AgSn3Se8 crystallizes in the tetragonal P4/nbm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. Ag(1) is bonded to four equivalent Se(1) atoms to form distorted AgSe4 tetrahedra that share edges with two equivalent Sn(1)Se4 tetrahedra. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form SnSe4 tetrahedra that share  an edgeedge with one Ag(1)Se4 tetrahedra and  an edgeedge with one Sn(2)Se4 tetrahedra. In the second Sn site, Sn(2) is bonded to four equivalent Se(2) atoms to form edge-sharing SnSe4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Ag(1), and one Sn(1) atom. In the second Se site, Se(2) is bonded to two equivalent K(1), one Sn(1), and one Sn(2) atom to form a mixture of edge and corner-sharing SeK2Sn2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3AgSn3Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.315
_cell_length_b   8.315
_cell_length_c   13.682
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   945.938
_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  0.500  0.500  0.274  1.0
  K  K1  1  0.000  0.000  0.726  1.0
  K  K2  1  0.000  0.000  0.000  1.0
  K  K3  1  0.500  0.500  0.726  1.0
  K  K4  1  0.000  0.000  0.274  1.0
  K  K5  1  0.500  0.500  0.000  1.0
  Ag  Ag6  1  0.000  0.500  0.000  1.0
  Ag  Ag7  1  0.500  0.000  0.000  1.0
  Sn  Sn8  1  0.000  0.500  0.241  1.0
  Sn  Sn9  1  0.000  0.500  0.759  1.0
  Sn  Sn10  1  0.500  0.000  0.500  1.0
  Sn  Sn11  1  0.500  0.000  0.241  1.0
  Sn  Sn12  1  0.500  0.000  0.759  1.0
  Sn  Sn13  1  0.000  0.500  0.500  1.0
  Se  Se14  1  0.322  0.178  0.862  1.0
  Se  Se15  1  0.335  0.165  0.374  1.0
  Se  Se16  1  0.822  0.322  0.862  1.0
  Se  Se17  1  0.822  0.678  0.138  1.0
  Se  Se18  1  0.335  0.835  0.626  1.0
  Se  Se19  1  0.322  0.822  0.138  1.0
  Se  Se20  1  0.665  0.165  0.626  1.0
  Se  Se21  1  0.165  0.335  0.626  1.0
  Se  Se22  1  0.835  0.335  0.374  1.0
  Se  Se23  1  0.665  0.835  0.374  1.0
  Se  Se24  1  0.178  0.322  0.138  1.0
  Se  Se25  1  0.178  0.678  0.862  1.0
  Se  Se26  1  0.835  0.665  0.626  1.0
  Se  Se27  1  0.678  0.822  0.862  1.0
  Se  Se28  1  0.678  0.178  0.138  1.0
  Se  Se29  1  0.165  0.665  0.374  1.0
[/CIF]
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The material described by K3AgSn3Se8 crystallizes in the tetragonal P4/nbm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. Ag(1) is bonded to four equivalent Se(1) atoms to form distorted AgSe4 tetrahedra that share edges with two equivalent Sn(1)Se4 tetrahedra. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form SnSe4 tetrahedra that share  an edgeedge with one Ag(1)Se4 tetrahedra and  an edgeedge with one Sn(2)Se4 tetrahedra. In the second Sn site, Sn(2) is bonded to four equivalent Se(2) atoms to form edge-sharing SnSe4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Ag(1), and one Sn(1) atom. In the second Se site, Se(2) is bonded to two equivalent K(1), one Sn(1), and one Sn(2) atom to form a mixture of edge and corner-sharing SeK2Sn2 trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3AgSn3Se8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.315
_cell_length_b   8.315
_cell_length_c   13.682
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   945.938
_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  0.500  0.500  0.274  1.0
  K  K1  1  0.000  0.000  0.726  1.0
  K  K2  1  0.000  0.000  0.000  1.0
  K  K3  1  0.500  0.500  0.726  1.0
  K  K4  1  0.000  0.000  0.274  1.0
  K  K5  1  0.500  0.500  0.000  1.0
  Ag  Ag6  1  0.000  0.500  0.000  1.0
  Ag  Ag7  1  0.500  0.000  0.000  1.0
  Sn  Sn8  1  0.000  0.500  0.241  1.0
  Sn  Sn9  1  0.000  0.500  0.759  1.0
  Sn  Sn10  1  0.500  0.000  0.500  1.0
  Sn  Sn11  1  0.500  0.000  0.241  1.0
  Sn  Sn12  1  0.500  0.000  0.759  1.0
  Sn  Sn13  1  0.000  0.500  0.500  1.0
  Se  Se14  1  0.322  0.178  0.862  1.0
  Se  Se15  1  0.335  0.165  0.374  1.0
  Se  Se16  1  0.822  0.322  0.862  1.0
  Se  Se17  1  0.822  0.678  0.138  1.0
  Se  Se18  1  0.335  0.835  0.626  1.0
  Se  Se19  1  0.322  0.822  0.138  1.0
  Se  Se20  1  0.665  0.165  0.626  1.0
  Se  Se21  1  0.165  0.335  0.626  1.0
  Se  Se22  1  0.835  0.335  0.374  1.0
  Se  Se23  1  0.665  0.835  0.374  1.0
  Se  Se24  1  0.178  0.322  0.138  1.0
  Se  Se25  1  0.178  0.678  0.862  1.0
  Se  Se26  1  0.835  0.665  0.626  1.0
  Se  Se27  1  0.678  0.822  0.862  1.0
  Se  Se28  1  0.678  0.178  0.138  1.0
  Se  Se29  1  0.165  0.665  0.374  1.0
[/CIF]
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