The crystal structure described by NaCr4O8 crystallizes in the tetragonal I4/m space group. Na(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. Cr(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of corner and edge-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are two inequivalent O sites. In the first O site, O(2) is bonded in a trigonal planar geometry to three equivalent Cr(1) atoms. In the second O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1) and three equivalent Cr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaCr4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.126
_cell_length_b   7.126
_cell_length_c   7.126
_cell_angle_alpha   92.520
_cell_angle_beta   92.520
_cell_angle_gamma   155.794
_symmetry_Int_Tables_number   1
_cell_volume   145.085
_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
  Na  Na0  1  0.500  0.500  0.000  1.0
  Cr  Cr1  1  0.348  0.165  0.513  1.0
  Cr  Cr2  1  0.835  0.348  0.182  1.0
  Cr  Cr3  1  0.165  0.652  0.818  1.0
  Cr  Cr4  1  0.652  0.835  0.487  1.0
  O  O5  1  0.848  0.801  0.649  1.0
  O  O6  1  0.837  0.540  0.377  1.0
  O  O7  1  0.199  0.848  0.047  1.0
  O  O8  1  0.540  0.163  0.703  1.0
  O  O9  1  0.460  0.837  0.297  1.0
  O  O10  1  0.801  0.152  0.953  1.0
  O  O11  1  0.163  0.460  0.623  1.0
  O  O12  1  0.152  0.199  0.351  1.0
[/CIF]
.
The crystal structure described by NaCr4O8 crystallizes in the tetragonal I4/m space group. Na(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. Cr(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of corner and edge-sharing CrO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are two inequivalent O sites. In the first O site, O(2) is bonded in a trigonal planar geometry to three equivalent Cr(1) atoms. In the second O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Na(1) and three equivalent Cr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaCr4O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.126
_cell_length_b   7.126
_cell_length_c   7.126
_cell_angle_alpha   92.520
_cell_angle_beta   92.520
_cell_angle_gamma   155.794
_symmetry_Int_Tables_number   1
_cell_volume   145.085
_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
  Na  Na0  1  0.500  0.500  0.000  1.0
  Cr  Cr1  1  0.348  0.165  0.513  1.0
  Cr  Cr2  1  0.835  0.348  0.182  1.0
  Cr  Cr3  1  0.165  0.652  0.818  1.0
  Cr  Cr4  1  0.652  0.835  0.487  1.0
  O  O5  1  0.848  0.801  0.649  1.0
  O  O6  1  0.837  0.540  0.377  1.0
  O  O7  1  0.199  0.848  0.047  1.0
  O  O8  1  0.540  0.163  0.703  1.0
  O  O9  1  0.460  0.837  0.297  1.0
  O  O10  1  0.801  0.152  0.953  1.0
  O  O11  1  0.163  0.460  0.623  1.0
  O  O12  1  0.152  0.199  0.351  1.0
[/CIF]
.