The material structure described by CaCO3 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(3), and three equivalent O(1) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three 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 3-coordinate geometry to two equivalent Ca(1) and one C(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one C(1) atom. is represented by the CIF file [CIF]
data_CaCO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.833
_cell_length_b   5.030
_cell_length_c   6.523
_cell_angle_alpha   95.891
_cell_angle_beta   106.061
_cell_angle_gamma   90.334
_symmetry_Int_Tables_number   1
_cell_volume   120.154
_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
  Ca  Ca0  1  0.605  0.315  0.256  1.0
  Ca  Ca1  1  0.395  0.685  0.744  1.0
  C  C2  1  0.991  0.198  0.749  1.0
  C  C3  1  0.009  0.802  0.251  1.0
  O  O4  1  0.817  0.383  0.641  1.0
  O  O5  1  0.183  0.617  0.359  1.0
  O  O6  1  0.877  0.953  0.709  1.0
  O  O7  1  0.123  0.047  0.291  1.0
  O  O8  1  0.294  0.267  0.891  1.0
  O  O9  1  0.706  0.733  0.109  1.0
[/CIF]
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The material structure described by CaCO3 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(3), and three equivalent O(1) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three 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 3-coordinate geometry to two equivalent Ca(1) and one C(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one C(1) atom. is represented by the CIF file [CIF]
data_CaCO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.833
_cell_length_b   5.030
_cell_length_c   6.523
_cell_angle_alpha   95.891
_cell_angle_beta   106.061
_cell_angle_gamma   90.334
_symmetry_Int_Tables_number   1
_cell_volume   120.154
_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
  Ca  Ca0  1  0.605  0.315  0.256  1.0
  Ca  Ca1  1  0.395  0.685  0.744  1.0
  C  C2  1  0.991  0.198  0.749  1.0
  C  C3  1  0.009  0.802  0.251  1.0
  O  O4  1  0.817  0.383  0.641  1.0
  O  O5  1  0.183  0.617  0.359  1.0
  O  O6  1  0.877  0.953  0.709  1.0
  O  O7  1  0.123  0.047  0.291  1.0
  O  O8  1  0.294  0.267  0.891  1.0
  O  O9  1  0.706  0.733  0.109  1.0
[/CIF]
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