The structure described by Na2CO3 crystallizes in the monoclinic C2/m space group. There are three 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 face-sharing NaO6 octahedra. In the second Na site, Na(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form face-sharing NaO6 octahedra. In the third Na site, Na(3) is bonded in a 8-coordinate geometry to one C(1), three equivalent O(2), and four equivalent O(1) atoms. C(1) is bonded in a trigonal planar geometry to one Na(3), one O(2), and two equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), two equivalent Na(3), and one C(1) atom. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Na(1), one Na(2), three equivalent Na(3), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.285
_cell_length_b   5.295
_cell_length_c   6.285
_cell_angle_alpha   94.930
_cell_angle_beta   90.000
_cell_angle_gamma   119.939
_symmetry_Int_Tables_number   1
_cell_volume   151.679
_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  0.000  0.000  1.0
  Na  Na1  1  0.000  0.000  0.500  1.0
  Na  Na2  1  0.674  0.348  0.771  1.0
  Na  Na3  1  0.326  0.652  0.229  1.0
  C  C4  1  0.670  0.339  0.245  1.0
  C  C5  1  0.330  0.661  0.755  1.0
  O  O6  1  0.814  0.202  0.260  1.0
  O  O7  1  0.388  0.202  0.260  1.0
  O  O8  1  0.186  0.798  0.740  1.0
  O  O9  1  0.612  0.798  0.740  1.0
  O  O10  1  0.808  0.615  0.212  1.0
  O  O11  1  0.192  0.385  0.788  1.0
[/CIF]
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The structure described by Na2CO3 crystallizes in the monoclinic C2/m space group. There are three 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 face-sharing NaO6 octahedra. In the second Na site, Na(2) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form face-sharing NaO6 octahedra. In the third Na site, Na(3) is bonded in a 8-coordinate geometry to one C(1), three equivalent O(2), and four equivalent O(1) atoms. C(1) is bonded in a trigonal planar geometry to one Na(3), one O(2), and two equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), two equivalent Na(3), and one C(1) atom. In the second O site, O(2) is bonded in a 1-coordinate geometry to one Na(1), one Na(2), three equivalent Na(3), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2CO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.285
_cell_length_b   5.295
_cell_length_c   6.285
_cell_angle_alpha   94.930
_cell_angle_beta   90.000
_cell_angle_gamma   119.939
_symmetry_Int_Tables_number   1
_cell_volume   151.679
_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  0.000  0.000  1.0
  Na  Na1  1  0.000  0.000  0.500  1.0
  Na  Na2  1  0.674  0.348  0.771  1.0
  Na  Na3  1  0.326  0.652  0.229  1.0
  C  C4  1  0.670  0.339  0.245  1.0
  C  C5  1  0.330  0.661  0.755  1.0
  O  O6  1  0.814  0.202  0.260  1.0
  O  O7  1  0.388  0.202  0.260  1.0
  O  O8  1  0.186  0.798  0.740  1.0
  O  O9  1  0.612  0.798  0.740  1.0
  O  O10  1  0.808  0.615  0.212  1.0
  O  O11  1  0.192  0.385  0.788  1.0
[/CIF]
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