The structure described by CaCO3 crystallizes in the orthorhombic Pnma space group. Ca(1) is bonded in a 9-coordinate geometry to three equivalent O(2) and six equivalent O(1) atoms. C(1) is bonded in a trigonal planar geometry to 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 distorted single-bond geometry to three equivalent Ca(1) and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Ca(1) and one C(1) atom. is represented by the CIF card [CIF]
data_CaCO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.016
_cell_length_b   5.812
_cell_length_c   8.035
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   234.244
_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
  Ca  Ca0  1  0.250  0.259  0.415  1.0
  Ca  Ca1  1  0.750  0.741  0.585  1.0
  Ca  Ca2  1  0.250  0.759  0.085  1.0
  Ca  Ca3  1  0.750  0.241  0.915  1.0
  C  C4  1  0.250  0.416  0.762  1.0
  C  C5  1  0.750  0.584  0.238  1.0
  C  C6  1  0.250  0.916  0.738  1.0
  C  C7  1  0.750  0.084  0.262  1.0
  O  O8  1  0.026  0.914  0.820  1.0
  O  O9  1  0.526  0.086  0.180  1.0
  O  O10  1  0.474  0.414  0.680  1.0
  O  O11  1  0.974  0.586  0.320  1.0
  O  O12  1  0.750  0.093  0.423  1.0
  O  O13  1  0.250  0.907  0.577  1.0
  O  O14  1  0.750  0.593  0.077  1.0
  O  O15  1  0.250  0.407  0.923  1.0
  O  O16  1  0.974  0.086  0.180  1.0
  O  O17  1  0.474  0.914  0.820  1.0
  O  O18  1  0.526  0.586  0.320  1.0
  O  O19  1  0.026  0.414  0.680  1.0
[/CIF]
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The structure described by CaCO3 crystallizes in the orthorhombic Pnma space group. Ca(1) is bonded in a 9-coordinate geometry to three equivalent O(2) and six equivalent O(1) atoms. C(1) is bonded in a trigonal planar geometry to 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 distorted single-bond geometry to three equivalent Ca(1) and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Ca(1) and one C(1) atom. is represented by the CIF card [CIF]
data_CaCO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.016
_cell_length_b   5.812
_cell_length_c   8.035
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   234.244
_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
  Ca  Ca0  1  0.250  0.259  0.415  1.0
  Ca  Ca1  1  0.750  0.741  0.585  1.0
  Ca  Ca2  1  0.250  0.759  0.085  1.0
  Ca  Ca3  1  0.750  0.241  0.915  1.0
  C  C4  1  0.250  0.416  0.762  1.0
  C  C5  1  0.750  0.584  0.238  1.0
  C  C6  1  0.250  0.916  0.738  1.0
  C  C7  1  0.750  0.084  0.262  1.0
  O  O8  1  0.026  0.914  0.820  1.0
  O  O9  1  0.526  0.086  0.180  1.0
  O  O10  1  0.474  0.414  0.680  1.0
  O  O11  1  0.974  0.586  0.320  1.0
  O  O12  1  0.750  0.093  0.423  1.0
  O  O13  1  0.250  0.907  0.577  1.0
  O  O14  1  0.750  0.593  0.077  1.0
  O  O15  1  0.250  0.407  0.923  1.0
  O  O16  1  0.974  0.086  0.180  1.0
  O  O17  1  0.474  0.914  0.820  1.0
  O  O18  1  0.526  0.586  0.320  1.0
  O  O19  1  0.026  0.414  0.680  1.0
[/CIF]
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