The crystal structure described by Na4CrO3 crystallizes in the monoclinic Cc space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. In the second Na site, Na(2) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form a mixture of distorted corner and edge-sharing NaO4 trigonal pyramids. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(2) atoms. In the fourth Na site, Na(4) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing NaO4 trigonal pyramids. Cr(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(1), one Na(3), one Na(4), two equivalent Na(2), and one Cr(1) atom. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Na(4), two equivalent Na(3), and one Cr(1) atom to form distorted corner-sharing ONa5Cr octahedra. The corner-sharing octahedral tilt angles are 56°. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(3), two equivalent Na(4), and one Cr(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4CrO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.832
_cell_length_b   6.176
_cell_length_c   8.822
_cell_angle_alpha   66.936
_cell_angle_beta   90.000
_cell_angle_gamma   61.823
_symmetry_Int_Tables_number   1
_cell_volume   250.906
_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  0.948  0.781  0.947  1.0
  Na  Na1  1  0.271  0.781  0.447  1.0
  Na  Na2  1  0.847  0.607  0.628  1.0
  Na  Na3  1  0.508  0.383  0.850  1.0
  Na  Na4  1  0.546  0.607  0.128  1.0
  Na  Na5  1  0.109  0.383  0.350  1.0
  Na  Na6  1  0.740  0.220  0.533  1.0
  Na  Na7  1  0.040  0.220  0.033  1.0
  Cr  Cr8  1  0.330  0.042  0.740  1.0
  Cr  Cr9  1  0.628  0.042  0.240  1.0
  O  O10  1  0.633  0.706  0.847  1.0
  O  O11  1  0.661  0.706  0.347  1.0
  O  O12  1  0.334  0.350  0.613  1.0
  O  O13  1  0.013  0.126  0.794  1.0
  O  O14  1  0.316  0.350  0.113  1.0
  O  O15  1  0.862  0.126  0.294  1.0
[/CIF]
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The crystal structure described by Na4CrO3 crystallizes in the monoclinic Cc space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. In the second Na site, Na(2) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form a mixture of distorted corner and edge-sharing NaO4 trigonal pyramids. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(2) atoms. In the fourth Na site, Na(4) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing NaO4 trigonal pyramids. Cr(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(1), one Na(3), one Na(4), two equivalent Na(2), and one Cr(1) atom. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Na(4), two equivalent Na(3), and one Cr(1) atom to form distorted corner-sharing ONa5Cr octahedra. The corner-sharing octahedral tilt angles are 56°. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Na(1), one Na(2), one Na(3), two equivalent Na(4), and one Cr(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4CrO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.832
_cell_length_b   6.176
_cell_length_c   8.822
_cell_angle_alpha   66.936
_cell_angle_beta   90.000
_cell_angle_gamma   61.823
_symmetry_Int_Tables_number   1
_cell_volume   250.906
_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  0.948  0.781  0.947  1.0
  Na  Na1  1  0.271  0.781  0.447  1.0
  Na  Na2  1  0.847  0.607  0.628  1.0
  Na  Na3  1  0.508  0.383  0.850  1.0
  Na  Na4  1  0.546  0.607  0.128  1.0
  Na  Na5  1  0.109  0.383  0.350  1.0
  Na  Na6  1  0.740  0.220  0.533  1.0
  Na  Na7  1  0.040  0.220  0.033  1.0
  Cr  Cr8  1  0.330  0.042  0.740  1.0
  Cr  Cr9  1  0.628  0.042  0.240  1.0
  O  O10  1  0.633  0.706  0.847  1.0
  O  O11  1  0.661  0.706  0.347  1.0
  O  O12  1  0.334  0.350  0.613  1.0
  O  O13  1  0.013  0.126  0.794  1.0
  O  O14  1  0.316  0.350  0.113  1.0
  O  O15  1  0.862  0.126  0.294  1.0
[/CIF]
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