The structure described by KNb(AgSe2)2 crystallizes in the orthorhombic Ama2 space group. K(1) is bonded in a distorted pentagonal planar geometry to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. Nb(1) is bonded to one Se(1), one Se(3), and two equivalent Se(2) atoms to form NbSe4 tetrahedra that share edges with two equivalent Ag(1)Se4 tetrahedra and edges with two equivalent Ag(2)Se4 tetrahedra. There are two inequivalent Ag sites. In the first Ag site, Ag(1) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form distorted AgSe4 tetrahedra that share corners with two equivalent Ag(1)Se4 tetrahedra, corners with four equivalent Ag(2)Se4 tetrahedra, and edges with two equivalent Nb(1)Se4 tetrahedra. In the second Ag site, Ag(2) is bonded to one Se(1), one Se(3), and two equivalent Se(2) atoms to form distorted AgSe4 tetrahedra that share corners with four equivalent Ag(1)Se4 tetrahedra and edges with two equivalent Nb(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one K(1), one Nb(1), one Ag(2), and two equivalent Ag(1) atoms. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one K(1), one Nb(1), one Ag(1), and one Ag(2) atom. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to two equivalent K(1), one Nb(1), and one Ag(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KNb(AgSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.443
_cell_length_b   10.443
_cell_length_c   8.324
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   145.816
_symmetry_Int_Tables_number   1
_cell_volume   510.073
_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  0.467  0.831  0.250  1.0
  K  K1  1  0.831  0.467  0.750  1.0
  Nb  Nb2  1  0.770  0.996  0.750  1.0
  Nb  Nb3  1  0.996  0.770  0.250  1.0
  Ag  Ag4  1  0.919  0.919  0.500  1.0
  Ag  Ag5  1  0.919  0.919  0.000  1.0
  Ag  Ag6  1  0.268  0.497  0.750  1.0
  Ag  Ag7  1  0.497  0.268  0.250  1.0
  Se  Se8  1  0.659  0.640  0.250  1.0
  Se  Se9  1  0.989  0.226  0.996  1.0
  Se  Se10  1  0.989  0.226  0.504  1.0
  Se  Se11  1  0.452  0.881  0.750  1.0
  Se  Se12  1  0.881  0.452  0.250  1.0
  Se  Se13  1  0.226  0.989  0.004  1.0
  Se  Se14  1  0.640  0.659  0.750  1.0
  Se  Se15  1  0.226  0.989  0.496  1.0
[/CIF]
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The structure described by KNb(AgSe2)2 crystallizes in the orthorhombic Ama2 space group. K(1) is bonded in a distorted pentagonal planar geometry to one Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. Nb(1) is bonded to one Se(1), one Se(3), and two equivalent Se(2) atoms to form NbSe4 tetrahedra that share edges with two equivalent Ag(1)Se4 tetrahedra and edges with two equivalent Ag(2)Se4 tetrahedra. There are two inequivalent Ag sites. In the first Ag site, Ag(1) is bonded to two equivalent Se(1) and two equivalent Se(2) atoms to form distorted AgSe4 tetrahedra that share corners with two equivalent Ag(1)Se4 tetrahedra, corners with four equivalent Ag(2)Se4 tetrahedra, and edges with two equivalent Nb(1)Se4 tetrahedra. In the second Ag site, Ag(2) is bonded to one Se(1), one Se(3), and two equivalent Se(2) atoms to form distorted AgSe4 tetrahedra that share corners with four equivalent Ag(1)Se4 tetrahedra and edges with two equivalent Nb(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to one K(1), one Nb(1), one Ag(2), and two equivalent Ag(1) atoms. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one K(1), one Nb(1), one Ag(1), and one Ag(2) atom. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to two equivalent K(1), one Nb(1), and one Ag(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KNb(AgSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.443
_cell_length_b   10.443
_cell_length_c   8.324
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   145.816
_symmetry_Int_Tables_number   1
_cell_volume   510.073
_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  0.467  0.831  0.250  1.0
  K  K1  1  0.831  0.467  0.750  1.0
  Nb  Nb2  1  0.770  0.996  0.750  1.0
  Nb  Nb3  1  0.996  0.770  0.250  1.0
  Ag  Ag4  1  0.919  0.919  0.500  1.0
  Ag  Ag5  1  0.919  0.919  0.000  1.0
  Ag  Ag6  1  0.268  0.497  0.750  1.0
  Ag  Ag7  1  0.497  0.268  0.250  1.0
  Se  Se8  1  0.659  0.640  0.250  1.0
  Se  Se9  1  0.989  0.226  0.996  1.0
  Se  Se10  1  0.989  0.226  0.504  1.0
  Se  Se11  1  0.452  0.881  0.750  1.0
  Se  Se12  1  0.881  0.452  0.250  1.0
  Se  Se13  1  0.226  0.989  0.004  1.0
  Se  Se14  1  0.640  0.659  0.750  1.0
  Se  Se15  1  0.226  0.989  0.496  1.0
[/CIF]
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