The structure described by Na2MnO3 is Caswellsilverite-like structured and crystallizes in the orthorhombic Fddd space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with five equivalent Na(2)O6 octahedra, and edges with five equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-18°. In the second Na site, Na(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with three equivalent Na(2)O6 octahedra, edges with four equivalent Mn(1)O6 octahedra, and edges with five equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-15°. Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, edges with four equivalent Na(2)O6 octahedra, and edges with five equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-15°. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 7-14°. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 6-10°. is represented by the CIF card [CIF]
data_Na2MnO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.893
_cell_length_b   9.440
_cell_length_c   5.344
_cell_angle_alpha   78.711
_cell_angle_beta   69.331
_cell_angle_gamma   31.972
_symmetry_Int_Tables_number   1
_cell_volume   241.772
_cell_formula_units_Z   4
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  0.994  0.994  0.506  1.0
  Na  Na1  1  0.423  0.423  0.577  1.0
  Na  Na2  1  0.827  0.827  0.673  1.0
  Na  Na3  1  0.256  0.256  0.744  1.0
  Na  Na4  1  0.744  0.744  0.256  1.0
  Na  Na5  1  0.673  0.673  0.827  1.0
  Na  Na6  1  0.577  0.577  0.423  1.0
  Na  Na7  1  0.506  0.506  0.994  1.0
  Mn  Mn8  1  0.916  0.916  0.084  1.0
  Mn  Mn9  1  0.334  0.334  0.166  1.0
  Mn  Mn10  1  0.166  0.166  0.334  1.0
  Mn  Mn11  1  0.084  0.084  0.916  1.0
  O  O12  1  0.155  0.658  0.297  1.0
  O  O13  1  0.658  0.155  0.890  1.0
  O  O14  1  0.095  0.592  0.953  1.0
  O  O15  1  0.592  0.095  0.360  1.0
  O  O16  1  0.054  0.446  0.446  1.0
  O  O17  1  0.446  0.054  0.054  1.0
  O  O18  1  0.360  0.953  0.592  1.0
  O  O19  1  0.953  0.360  0.095  1.0
  O  O20  1  0.890  0.297  0.658  1.0
  O  O21  1  0.297  0.890  0.155  1.0
  O  O22  1  0.196  0.804  0.804  1.0
  O  O23  1  0.804  0.196  0.196  1.0
[/CIF]
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The structure described by Na2MnO3 is Caswellsilverite-like structured and crystallizes in the orthorhombic Fddd space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with five equivalent Na(2)O6 octahedra, and edges with five equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-18°. In the second Na site, Na(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with three equivalent Na(2)O6 octahedra, edges with four equivalent Mn(1)O6 octahedra, and edges with five equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-15°. Mn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with four equivalent Na(2)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, edges with four equivalent Na(2)O6 octahedra, and edges with five equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-15°. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 7-14°. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 6-10°. is represented by the CIF card [CIF]
data_Na2MnO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.893
_cell_length_b   9.440
_cell_length_c   5.344
_cell_angle_alpha   78.711
_cell_angle_beta   69.331
_cell_angle_gamma   31.972
_symmetry_Int_Tables_number   1
_cell_volume   241.772
_cell_formula_units_Z   4
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  0.994  0.994  0.506  1.0
  Na  Na1  1  0.423  0.423  0.577  1.0
  Na  Na2  1  0.827  0.827  0.673  1.0
  Na  Na3  1  0.256  0.256  0.744  1.0
  Na  Na4  1  0.744  0.744  0.256  1.0
  Na  Na5  1  0.673  0.673  0.827  1.0
  Na  Na6  1  0.577  0.577  0.423  1.0
  Na  Na7  1  0.506  0.506  0.994  1.0
  Mn  Mn8  1  0.916  0.916  0.084  1.0
  Mn  Mn9  1  0.334  0.334  0.166  1.0
  Mn  Mn10  1  0.166  0.166  0.334  1.0
  Mn  Mn11  1  0.084  0.084  0.916  1.0
  O  O12  1  0.155  0.658  0.297  1.0
  O  O13  1  0.658  0.155  0.890  1.0
  O  O14  1  0.095  0.592  0.953  1.0
  O  O15  1  0.592  0.095  0.360  1.0
  O  O16  1  0.054  0.446  0.446  1.0
  O  O17  1  0.446  0.054  0.054  1.0
  O  O18  1  0.360  0.953  0.592  1.0
  O  O19  1  0.953  0.360  0.095  1.0
  O  O20  1  0.890  0.297  0.658  1.0
  O  O21  1  0.297  0.890  0.155  1.0
  O  O22  1  0.196  0.804  0.804  1.0
  O  O23  1  0.804  0.196  0.196  1.0
[/CIF]
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