The material described by Nb6AgSe8 crystallizes in the trigonal P-3 space group. Nb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. Ag(1) is bonded in a 6-coordinate geometry to six equivalent Se(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded to six equivalent Nb(1) atoms to form distorted face-sharing SeNb6 pentagonal pyramids. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to four equivalent Nb(1) and one Ag(1) atom. is represented by the CIF file [CIF]
data_Nb6AgSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.115
_cell_length_b   10.115
_cell_length_c   3.485
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   308.772
_cell_formula_units_Z   1
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
  Nb  Nb0  1  0.108  0.621  0.250  1.0
  Nb  Nb1  1  0.513  0.892  0.250  1.0
  Nb  Nb2  1  0.379  0.487  0.250  1.0
  Nb  Nb3  1  0.892  0.379  0.750  1.0
  Nb  Nb4  1  0.487  0.108  0.750  1.0
  Nb  Nb5  1  0.621  0.513  0.750  1.0
  Ag  Ag6  1  0.000  0.000  0.500  1.0
  Se  Se7  1  0.278  0.941  0.250  1.0
  Se  Se8  1  0.663  0.722  0.250  1.0
  Se  Se9  1  0.059  0.337  0.250  1.0
  Se  Se10  1  0.722  0.059  0.750  1.0
  Se  Se11  1  0.337  0.278  0.750  1.0
  Se  Se12  1  0.941  0.663  0.750  1.0
  Se  Se13  1  0.667  0.333  0.250  1.0
  Se  Se14  1  0.333  0.667  0.750  1.0
[/CIF]
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The material described by Nb6AgSe8 crystallizes in the trigonal P-3 space group. Nb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. Ag(1) is bonded in a 6-coordinate geometry to six equivalent Se(1) atoms. There are two inequivalent Se sites. In the first Se site, Se(2) is bonded to six equivalent Nb(1) atoms to form distorted face-sharing SeNb6 pentagonal pyramids. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to four equivalent Nb(1) and one Ag(1) atom. is represented by the CIF file [CIF]
data_Nb6AgSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.115
_cell_length_b   10.115
_cell_length_c   3.485
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   308.772
_cell_formula_units_Z   1
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
  Nb  Nb0  1  0.108  0.621  0.250  1.0
  Nb  Nb1  1  0.513  0.892  0.250  1.0
  Nb  Nb2  1  0.379  0.487  0.250  1.0
  Nb  Nb3  1  0.892  0.379  0.750  1.0
  Nb  Nb4  1  0.487  0.108  0.750  1.0
  Nb  Nb5  1  0.621  0.513  0.750  1.0
  Ag  Ag6  1  0.000  0.000  0.500  1.0
  Se  Se7  1  0.278  0.941  0.250  1.0
  Se  Se8  1  0.663  0.722  0.250  1.0
  Se  Se9  1  0.059  0.337  0.250  1.0
  Se  Se10  1  0.722  0.059  0.750  1.0
  Se  Se11  1  0.337  0.278  0.750  1.0
  Se  Se12  1  0.941  0.663  0.750  1.0
  Se  Se13  1  0.667  0.333  0.250  1.0
  Se  Se14  1  0.333  0.667  0.750  1.0
[/CIF]
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