The structure described by FeNb3S6 is Ilmenite-like structured and crystallizes in the hexagonal P6_322 space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to six equivalent S(1) atoms to form distorted NbS6 pentagonal pyramids that share corners with six equivalent Fe(1)S6 octahedra and edges with six equivalent Nb(2)S6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 46°. In the second Nb site, Nb(2) is bonded to six equivalent S(1) atoms to form distorted NbS6 pentagonal pyramids that share corners with three equivalent Fe(1)S6 octahedra, edges with three equivalent Nb(1)S6 pentagonal pyramids, edges with three equivalent Nb(2)S6 pentagonal pyramids, and  a faceface with one Fe(1)S6 octahedra. The corner-sharing octahedral tilt angles are 47°. Fe(1) is bonded to six equivalent S(1) atoms to form FeS6 octahedra that share corners with six equivalent Nb(1)S6 pentagonal pyramids, corners with six equivalent Nb(2)S6 pentagonal pyramids, and faces with two equivalent Nb(2)S6 pentagonal pyramids. S(1) is bonded in a rectangular see-saw-like geometry to one Nb(1), two equivalent Nb(2), and one Fe(1) atom. is represented by the CIF file [CIF]
data_Nb3FeS6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.786
_cell_length_b   5.786
_cell_length_c   11.781
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   341.588
_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
  Nb  Nb0  1  1.000  0.000  0.500  1.0
  Nb  Nb1  1  0.000  1.000  1.000  1.0
  Nb  Nb2  1  0.333  0.667  0.994  1.0
  Nb  Nb3  1  0.667  0.333  0.005  1.0
  Nb  Nb4  1  0.667  0.333  0.495  1.0
  Nb  Nb5  1  0.333  0.667  0.506  1.0
  Fe  Fe6  1  0.333  0.667  0.250  1.0
  Fe  Fe7  1  0.667  0.333  0.750  1.0
  S  S8  1  0.331  0.339  0.366  1.0
  S  S9  1  0.661  0.992  0.366  1.0
  S  S10  1  0.008  0.669  0.366  1.0
  S  S11  1  0.339  0.331  0.634  1.0
  S  S12  1  0.992  0.661  0.634  1.0
  S  S13  1  0.669  0.008  0.634  1.0
  S  S14  1  0.669  0.661  0.866  1.0
  S  S15  1  0.339  0.008  0.866  1.0
  S  S16  1  0.992  0.331  0.866  1.0
  S  S17  1  0.661  0.669  0.134  1.0
  S  S18  1  0.008  0.339  0.134  1.0
  S  S19  1  0.331  0.992  0.134  1.0
[/CIF]
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The structure described by FeNb3S6 is Ilmenite-like structured and crystallizes in the hexagonal P6_322 space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to six equivalent S(1) atoms to form distorted NbS6 pentagonal pyramids that share corners with six equivalent Fe(1)S6 octahedra and edges with six equivalent Nb(2)S6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 46°. In the second Nb site, Nb(2) is bonded to six equivalent S(1) atoms to form distorted NbS6 pentagonal pyramids that share corners with three equivalent Fe(1)S6 octahedra, edges with three equivalent Nb(1)S6 pentagonal pyramids, edges with three equivalent Nb(2)S6 pentagonal pyramids, and  a faceface with one Fe(1)S6 octahedra. The corner-sharing octahedral tilt angles are 47°. Fe(1) is bonded to six equivalent S(1) atoms to form FeS6 octahedra that share corners with six equivalent Nb(1)S6 pentagonal pyramids, corners with six equivalent Nb(2)S6 pentagonal pyramids, and faces with two equivalent Nb(2)S6 pentagonal pyramids. S(1) is bonded in a rectangular see-saw-like geometry to one Nb(1), two equivalent Nb(2), and one Fe(1) atom. is represented by the CIF file [CIF]
data_Nb3FeS6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.786
_cell_length_b   5.786
_cell_length_c   11.781
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   341.588
_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
  Nb  Nb0  1  1.000  0.000  0.500  1.0
  Nb  Nb1  1  0.000  1.000  1.000  1.0
  Nb  Nb2  1  0.333  0.667  0.994  1.0
  Nb  Nb3  1  0.667  0.333  0.005  1.0
  Nb  Nb4  1  0.667  0.333  0.495  1.0
  Nb  Nb5  1  0.333  0.667  0.506  1.0
  Fe  Fe6  1  0.333  0.667  0.250  1.0
  Fe  Fe7  1  0.667  0.333  0.750  1.0
  S  S8  1  0.331  0.339  0.366  1.0
  S  S9  1  0.661  0.992  0.366  1.0
  S  S10  1  0.008  0.669  0.366  1.0
  S  S11  1  0.339  0.331  0.634  1.0
  S  S12  1  0.992  0.661  0.634  1.0
  S  S13  1  0.669  0.008  0.634  1.0
  S  S14  1  0.669  0.661  0.866  1.0
  S  S15  1  0.339  0.008  0.866  1.0
  S  S16  1  0.992  0.331  0.866  1.0
  S  S17  1  0.661  0.669  0.134  1.0
  S  S18  1  0.008  0.339  0.134  1.0
  S  S19  1  0.331  0.992  0.134  1.0
[/CIF]
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