The compound described by Na3CrCl6 is Ilmenite-like structured and crystallizes in the trigonal P-31c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to six equivalent Cl(1) atoms to form NaCl6 octahedra that share corners with twelve equivalent Na(2)Cl6 pentagonal pyramids and edges with three equivalent Cr(1)Cl6 octahedra. In the second Na site, Na(2) is bonded to six equivalent Cl(1) atoms to form distorted NaCl6 pentagonal pyramids that share corners with three equivalent Cr(1)Cl6 octahedra, corners with six equivalent Na(1)Cl6 octahedra, edges with three equivalent Na(2)Cl6 pentagonal pyramids, and  a faceface with one Cr(1)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 42-65°. Cr(1) is bonded to six equivalent Cl(1) atoms to form CrCl6 octahedra that share corners with six equivalent Na(2)Cl6 pentagonal pyramids, edges with three equivalent Na(1)Cl6 octahedra, and faces with two equivalent Na(2)Cl6 pentagonal pyramids. Cl(1) is bonded in a distorted see-saw-like geometry to one Na(1), two equivalent Na(2), and one Cr(1) atom. is represented by the CIF card [CIF]
data_Na3CrCl6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.783
_cell_length_b   6.783
_cell_length_c   11.974
_cell_angle_alpha   89.999
_cell_angle_beta   89.999
_cell_angle_gamma   120.006
_symmetry_Int_Tables_number   1
_cell_volume   477.128
_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
  Na  Na0  1  0.000  1.000  0.750  1.0
  Na  Na1  1  1.000  0.000  0.250  1.0
  Na  Na2  1  0.667  0.333  0.457  1.0
  Na  Na3  1  0.667  0.333  0.043  1.0
  Na  Na4  1  0.333  0.667  0.543  1.0
  Na  Na5  1  0.333  0.667  0.957  1.0
  Cr  Cr6  1  0.333  0.667  0.250  1.0
  Cr  Cr7  1  0.667  0.333  0.750  1.0
  Cl  Cl8  1  0.379  0.322  0.866  1.0
  Cl  Cl9  1  0.943  0.621  0.866  1.0
  Cl  Cl10  1  0.379  0.057  0.634  1.0
  Cl  Cl11  1  0.943  0.323  0.634  1.0
  Cl  Cl12  1  0.323  0.943  0.134  1.0
  Cl  Cl13  1  0.678  0.621  0.634  1.0
  Cl  Cl14  1  0.057  0.379  0.134  1.0
  Cl  Cl15  1  0.621  0.678  0.134  1.0
  Cl  Cl16  1  0.322  0.379  0.366  1.0
  Cl  Cl17  1  0.621  0.943  0.366  1.0
  Cl  Cl18  1  0.057  0.677  0.366  1.0
  Cl  Cl19  1  0.677  0.057  0.866  1.0
[/CIF]
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The compound described by Na3CrCl6 is Ilmenite-like structured and crystallizes in the trigonal P-31c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to six equivalent Cl(1) atoms to form NaCl6 octahedra that share corners with twelve equivalent Na(2)Cl6 pentagonal pyramids and edges with three equivalent Cr(1)Cl6 octahedra. In the second Na site, Na(2) is bonded to six equivalent Cl(1) atoms to form distorted NaCl6 pentagonal pyramids that share corners with three equivalent Cr(1)Cl6 octahedra, corners with six equivalent Na(1)Cl6 octahedra, edges with three equivalent Na(2)Cl6 pentagonal pyramids, and  a faceface with one Cr(1)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 42-65°. Cr(1) is bonded to six equivalent Cl(1) atoms to form CrCl6 octahedra that share corners with six equivalent Na(2)Cl6 pentagonal pyramids, edges with three equivalent Na(1)Cl6 octahedra, and faces with two equivalent Na(2)Cl6 pentagonal pyramids. Cl(1) is bonded in a distorted see-saw-like geometry to one Na(1), two equivalent Na(2), and one Cr(1) atom. is represented by the CIF card [CIF]
data_Na3CrCl6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.783
_cell_length_b   6.783
_cell_length_c   11.974
_cell_angle_alpha   89.999
_cell_angle_beta   89.999
_cell_angle_gamma   120.006
_symmetry_Int_Tables_number   1
_cell_volume   477.128
_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
  Na  Na0  1  0.000  1.000  0.750  1.0
  Na  Na1  1  1.000  0.000  0.250  1.0
  Na  Na2  1  0.667  0.333  0.457  1.0
  Na  Na3  1  0.667  0.333  0.043  1.0
  Na  Na4  1  0.333  0.667  0.543  1.0
  Na  Na5  1  0.333  0.667  0.957  1.0
  Cr  Cr6  1  0.333  0.667  0.250  1.0
  Cr  Cr7  1  0.667  0.333  0.750  1.0
  Cl  Cl8  1  0.379  0.322  0.866  1.0
  Cl  Cl9  1  0.943  0.621  0.866  1.0
  Cl  Cl10  1  0.379  0.057  0.634  1.0
  Cl  Cl11  1  0.943  0.323  0.634  1.0
  Cl  Cl12  1  0.323  0.943  0.134  1.0
  Cl  Cl13  1  0.678  0.621  0.634  1.0
  Cl  Cl14  1  0.057  0.379  0.134  1.0
  Cl  Cl15  1  0.621  0.678  0.134  1.0
  Cl  Cl16  1  0.322  0.379  0.366  1.0
  Cl  Cl17  1  0.621  0.943  0.366  1.0
  Cl  Cl18  1  0.057  0.677  0.366  1.0
  Cl  Cl19  1  0.677  0.057  0.866  1.0
[/CIF]
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