The compound described by Na2CO3.H2O crystallizes in the orthorhombic Pca2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(1), and two equivalent O(2) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(4) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(4) atom. There are four inequivalent O sites. In the first O site, O(4) is bonded in a distorted water-like geometry to one Na(1), one Na(2), one H(1), and one H(2) atom. In the second O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Na(2), and one C(1) atom. In the third O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Na(1), two equivalent Na(2), and one C(1) atom. In the fourth O site, O(3) is bonded in a 1-coordinate geometry to two equivalent Na(1) and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2H2CO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.282
_cell_length_b   6.489
_cell_length_c   10.777
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   369.383
_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  0.860  1.000  0.693  1.0
  Na  Na1  1  0.140  0.500  0.307  1.0
  Na  Na2  1  0.860  0.500  0.807  1.0
  Na  Na3  1  0.140  1.000  0.193  1.0
  Na  Na4  1  0.378  0.064  0.501  1.0
  Na  Na5  1  0.622  0.564  0.499  1.0
  Na  Na6  1  0.378  0.564  0.999  1.0
  Na  Na7  1  0.622  0.064  0.001  1.0
  H  H8  1  0.837  0.148  0.434  1.0
  H  H9  1  0.163  0.648  0.566  1.0
  H  H10  1  0.837  0.648  0.066  1.0
  H  H11  1  0.163  0.148  0.934  1.0
  H  H12  1  0.900  0.918  0.409  1.0
  H  H13  1  0.100  0.418  0.591  1.0
  H  H14  1  0.900  0.418  0.091  1.0
  H  H15  1  0.100  0.918  0.909  1.0
  C  C16  1  0.398  0.785  0.755  1.0
  C  C17  1  0.602  0.285  0.245  1.0
  C  C18  1  0.398  0.285  0.745  1.0
  C  C19  1  0.602  0.785  0.255  1.0
  O  O20  1  0.453  0.799  0.638  1.0
  O  O21  1  0.547  0.299  0.362  1.0
  O  O22  1  0.453  0.299  0.862  1.0
  O  O23  1  0.547  0.799  0.138  1.0
  O  O24  1  0.575  0.797  0.837  1.0
  O  O25  1  0.425  0.297  0.163  1.0
  O  O26  1  0.575  0.297  0.663  1.0
  O  O27  1  0.425  0.797  0.337  1.0
  O  O28  1  0.162  0.761  0.789  1.0
  O  O29  1  0.838  0.261  0.211  1.0
  O  O30  1  0.162  0.261  0.711  1.0
  O  O31  1  0.838  0.761  0.289  1.0
  O  O32  1  0.932  0.032  0.471  1.0
  O  O33  1  0.068  0.532  0.529  1.0
  O  O34  1  0.932  0.532  0.029  1.0
  O  O35  1  0.068  0.032  0.971  1.0
[/CIF]
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The compound described by Na2CO3.H2O crystallizes in the orthorhombic Pca2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(4), two equivalent O(1), and two equivalent O(2) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(4) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(4) atom. There are four inequivalent O sites. In the first O site, O(4) is bonded in a distorted water-like geometry to one Na(1), one Na(2), one H(1), and one H(2) atom. In the second O site, O(1) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Na(2), and one C(1) atom. In the third O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Na(1), two equivalent Na(2), and one C(1) atom. In the fourth O site, O(3) is bonded in a 1-coordinate geometry to two equivalent Na(1) and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na2H2CO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.282
_cell_length_b   6.489
_cell_length_c   10.777
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   369.383
_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  0.860  1.000  0.693  1.0
  Na  Na1  1  0.140  0.500  0.307  1.0
  Na  Na2  1  0.860  0.500  0.807  1.0
  Na  Na3  1  0.140  1.000  0.193  1.0
  Na  Na4  1  0.378  0.064  0.501  1.0
  Na  Na5  1  0.622  0.564  0.499  1.0
  Na  Na6  1  0.378  0.564  0.999  1.0
  Na  Na7  1  0.622  0.064  0.001  1.0
  H  H8  1  0.837  0.148  0.434  1.0
  H  H9  1  0.163  0.648  0.566  1.0
  H  H10  1  0.837  0.648  0.066  1.0
  H  H11  1  0.163  0.148  0.934  1.0
  H  H12  1  0.900  0.918  0.409  1.0
  H  H13  1  0.100  0.418  0.591  1.0
  H  H14  1  0.900  0.418  0.091  1.0
  H  H15  1  0.100  0.918  0.909  1.0
  C  C16  1  0.398  0.785  0.755  1.0
  C  C17  1  0.602  0.285  0.245  1.0
  C  C18  1  0.398  0.285  0.745  1.0
  C  C19  1  0.602  0.785  0.255  1.0
  O  O20  1  0.453  0.799  0.638  1.0
  O  O21  1  0.547  0.299  0.362  1.0
  O  O22  1  0.453  0.299  0.862  1.0
  O  O23  1  0.547  0.799  0.138  1.0
  O  O24  1  0.575  0.797  0.837  1.0
  O  O25  1  0.425  0.297  0.163  1.0
  O  O26  1  0.575  0.297  0.663  1.0
  O  O27  1  0.425  0.797  0.337  1.0
  O  O28  1  0.162  0.761  0.789  1.0
  O  O29  1  0.838  0.261  0.211  1.0
  O  O30  1  0.162  0.261  0.711  1.0
  O  O31  1  0.838  0.761  0.289  1.0
  O  O32  1  0.932  0.032  0.471  1.0
  O  O33  1  0.068  0.532  0.529  1.0
  O  O34  1  0.932  0.532  0.029  1.0
  O  O35  1  0.068  0.032  0.971  1.0
[/CIF]
.