The crystal structure described by CaCO3 is Calcite-like structured and crystallizes in the monoclinic C2 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(4) atoms to form corner-sharing CaO6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the second Ca site, Ca(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted corner-sharing CaO6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 59-63°. There are two inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(5) and two equivalent O(4) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ca(1), one Ca(2), and one C(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ca(1), one Ca(2), and one C(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(1), one Ca(2), and one C(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Ca(1) and one C(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Ca(1) and one C(2) atom. is represented by the CIF card [CIF]
data_CaCO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.041
_cell_length_b   5.041
_cell_length_c   8.745
_cell_angle_alpha   89.355
_cell_angle_beta   89.355
_cell_angle_gamma   59.597
_symmetry_Int_Tables_number   1
_cell_volume   191.628
_cell_formula_units_Z   3
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  0.347  0.323  0.334  1.0
  Ca  Ca1  1  0.017  0.983  0.000  1.0
  Ca  Ca2  1  0.677  0.653  0.666  1.0
  C  C3  1  0.689  0.651  0.169  1.0
  C  C4  1  0.349  0.311  0.831  1.0
  C  C5  1  0.009  0.991  0.500  1.0
  O  O6  1  0.609  0.051  0.834  1.0
  O  O7  1  0.092  0.310  0.826  1.0
  O  O8  1  0.348  0.569  0.833  1.0
  O  O9  1  0.431  0.652  0.167  1.0
  O  O10  1  0.009  0.733  0.500  1.0
  O  O11  1  0.267  0.991  0.500  1.0
  O  O12  1  0.690  0.908  0.174  1.0
  O  O13  1  0.949  0.391  0.166  1.0
  O  O14  1  0.749  0.251  0.500  1.0
[/CIF]
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The crystal structure described by CaCO3 is Calcite-like structured and crystallizes in the monoclinic C2 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(2), one O(3), one O(5), and two equivalent O(4) atoms to form corner-sharing CaO6 octahedra. The corner-sharing octahedral tilt angles range from 60-62°. In the second Ca site, Ca(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted corner-sharing CaO6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 59-63°. There are two inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(5) and two equivalent O(4) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ca(1), one Ca(2), and one C(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ca(1), one Ca(2), and one C(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(1), one Ca(2), and one C(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Ca(1) and one C(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Ca(1) and one C(2) atom. is represented by the CIF card [CIF]
data_CaCO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.041
_cell_length_b   5.041
_cell_length_c   8.745
_cell_angle_alpha   89.355
_cell_angle_beta   89.355
_cell_angle_gamma   59.597
_symmetry_Int_Tables_number   1
_cell_volume   191.628
_cell_formula_units_Z   3
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  0.347  0.323  0.334  1.0
  Ca  Ca1  1  0.017  0.983  0.000  1.0
  Ca  Ca2  1  0.677  0.653  0.666  1.0
  C  C3  1  0.689  0.651  0.169  1.0
  C  C4  1  0.349  0.311  0.831  1.0
  C  C5  1  0.009  0.991  0.500  1.0
  O  O6  1  0.609  0.051  0.834  1.0
  O  O7  1  0.092  0.310  0.826  1.0
  O  O8  1  0.348  0.569  0.833  1.0
  O  O9  1  0.431  0.652  0.167  1.0
  O  O10  1  0.009  0.733  0.500  1.0
  O  O11  1  0.267  0.991  0.500  1.0
  O  O12  1  0.690  0.908  0.174  1.0
  O  O13  1  0.949  0.391  0.166  1.0
  O  O14  1  0.749  0.251  0.500  1.0
[/CIF]
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