The compound described by CaCO3 crystallizes in the orthorhombic C222_1 space group. Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(1) and six equivalent O(2) atoms. C(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing CO4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent Ca(1) and two equivalent C(1) atoms. In the second O site, O(2) is bonded in a 1-coordinate geometry to three equivalent Ca(1) and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaCO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.419
_cell_length_b   5.419
_cell_length_c   3.786
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.566
_symmetry_Int_Tables_number   1
_cell_volume   104.749
_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  0.195  0.805  0.750  1.0
  Ca  Ca1  1  0.805  0.195  0.250  1.0
  C  C2  1  0.641  0.641  0.000  1.0
  C  C3  1  0.359  0.359  0.500  1.0
  O  O4  1  0.583  0.417  0.750  1.0
  O  O5  1  0.417  0.583  0.250  1.0
  O  O6  1  0.134  0.352  0.663  1.0
  O  O7  1  0.352  0.134  0.337  1.0
  O  O8  1  0.866  0.648  0.163  1.0
  O  O9  1  0.648  0.866  0.837  1.0
[/CIF]
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The compound described by CaCO3 crystallizes in the orthorhombic C222_1 space group. Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(1) and six equivalent O(2) atoms. C(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing CO4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent Ca(1) and two equivalent C(1) atoms. In the second O site, O(2) is bonded in a 1-coordinate geometry to three equivalent Ca(1) and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaCO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.419
_cell_length_b   5.419
_cell_length_c   3.786
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.566
_symmetry_Int_Tables_number   1
_cell_volume   104.749
_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  0.195  0.805  0.750  1.0
  Ca  Ca1  1  0.805  0.195  0.250  1.0
  C  C2  1  0.641  0.641  0.000  1.0
  C  C3  1  0.359  0.359  0.500  1.0
  O  O4  1  0.583  0.417  0.750  1.0
  O  O5  1  0.417  0.583  0.250  1.0
  O  O6  1  0.134  0.352  0.663  1.0
  O  O7  1  0.352  0.134  0.337  1.0
  O  O8  1  0.866  0.648  0.163  1.0
  O  O9  1  0.648  0.866  0.837  1.0
[/CIF]
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