The material structure described by Na2Ca2(CO3)3 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(4) atoms. Ca(1) is bonded in a 9-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), and four equivalent O(4) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(2) and two equivalent O(4) atoms. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(3) and two equivalent O(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), two equivalent Ca(1), and one C(2) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Ca(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Na(1), two equivalent Ca(1), and one C(2) atom. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), two equivalent Ca(1), and one C(1) atom to form a mixture of distorted edge, face, and corner-sharing ONa2Ca2C trigonal bipyramids. is represented by the CIF file [CIF]
data_Na2Ca2(CO3)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.638
_cell_length_b   6.638
_cell_length_c   5.007
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   114.344
_symmetry_Int_Tables_number   1
_cell_volume   201.031
_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  0.074  0.074  0.000  1.0
  Na  Na1  1  0.388  0.388  0.500  1.0
  Ca  Ca2  1  0.785  0.218  0.500  1.0
  Ca  Ca3  1  0.218  0.785  0.500  1.0
  C  C4  1  0.126  0.534  0.000  1.0
  C  C5  1  0.534  0.126  0.000  1.0
  C  C6  1  0.774  0.774  0.500  1.0
  O  O7  1  0.587  0.790  0.500  1.0
  O  O8  1  0.790  0.587  0.500  1.0
  O  O9  1  0.123  0.728  0.000  1.0
  O  O10  1  0.958  0.958  0.500  1.0
  O  O11  1  0.728  0.123  0.000  1.0
  O  O12  1  0.130  0.439  0.774  1.0
  O  O13  1  0.439  0.130  0.226  1.0
  O  O14  1  0.130  0.439  0.226  1.0
  O  O15  1  0.439  0.130  0.774  1.0
[/CIF]
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The material structure described by Na2Ca2(CO3)3 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(4) atoms. Ca(1) is bonded in a 9-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), and four equivalent O(4) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(2) and two equivalent O(4) atoms. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(3) and two equivalent O(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Na(2), two equivalent Ca(1), and one C(2) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Ca(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Na(1), two equivalent Ca(1), and one C(2) atom. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), two equivalent Ca(1), and one C(1) atom to form a mixture of distorted edge, face, and corner-sharing ONa2Ca2C trigonal bipyramids. is represented by the CIF file [CIF]
data_Na2Ca2(CO3)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.638
_cell_length_b   6.638
_cell_length_c   5.007
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   114.344
_symmetry_Int_Tables_number   1
_cell_volume   201.031
_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  0.074  0.074  0.000  1.0
  Na  Na1  1  0.388  0.388  0.500  1.0
  Ca  Ca2  1  0.785  0.218  0.500  1.0
  Ca  Ca3  1  0.218  0.785  0.500  1.0
  C  C4  1  0.126  0.534  0.000  1.0
  C  C5  1  0.534  0.126  0.000  1.0
  C  C6  1  0.774  0.774  0.500  1.0
  O  O7  1  0.587  0.790  0.500  1.0
  O  O8  1  0.790  0.587  0.500  1.0
  O  O9  1  0.123  0.728  0.000  1.0
  O  O10  1  0.958  0.958  0.500  1.0
  O  O11  1  0.728  0.123  0.000  1.0
  O  O12  1  0.130  0.439  0.774  1.0
  O  O13  1  0.439  0.130  0.226  1.0
  O  O14  1  0.130  0.439  0.226  1.0
  O  O15  1  0.439  0.130  0.774  1.0
[/CIF]
.