The compound described by CaC2O4 crystallizes in the monoclinic P2/m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted edge-sharing CaO7 pentagonal bipyramids. In the second Ca site, Ca(2) is bonded to one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form distorted edge-sharing CaO7 pentagonal bipyramids. There are four inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to two equivalent O(1) atoms. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to two equivalent O(2) atoms. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(4) atom. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted 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 distorted trigonal planar geometry to one Ca(1), one Ca(2), and one C(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one C(3) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Ca(1) and one C(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Ca(2) and one C(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Ca(2) and one C(4) atom. is represented by the CIF file [CIF]
data_Ca(CO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.487
_cell_length_b   6.237
_cell_length_c   9.668
_cell_angle_alpha   89.118
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   451.360
_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  0.500  0.405  0.181  1.0
  Ca  Ca1  1  0.500  0.595  0.819  1.0
  Ca  Ca2  1  0.000  0.586  0.680  1.0
  Ca  Ca3  1  0.000  0.414  0.320  1.0
  C  C4  1  0.895  0.500  0.000  1.0
  C  C5  1  0.395  0.500  0.500  1.0
  C  C6  1  0.500  0.931  0.068  1.0
  C  C7  1  0.105  0.500  0.000  1.0
  C  C8  1  0.605  0.500  0.500  1.0
  C  C9  1  0.000  0.065  0.569  1.0
  C  C10  1  0.500  0.069  0.932  1.0
  C  C11  1  0.000  0.935  0.431  1.0
  O  O12  1  0.180  0.548  0.886  1.0
  O  O13  1  0.180  0.452  0.114  1.0
  O  O14  1  0.820  0.452  0.114  1.0
  O  O15  1  0.680  0.548  0.613  1.0
  O  O16  1  0.500  0.729  0.052  1.0
  O  O17  1  0.320  0.548  0.613  1.0
  O  O18  1  0.500  0.027  0.182  1.0
  O  O19  1  0.000  0.037  0.318  1.0
  O  O20  1  0.320  0.452  0.387  1.0
  O  O21  1  0.680  0.452  0.387  1.0
  O  O22  1  0.000  0.963  0.682  1.0
  O  O23  1  0.500  0.973  0.818  1.0
  O  O24  1  0.500  0.271  0.948  1.0
  O  O25  1  0.000  0.732  0.447  1.0
  O  O26  1  0.000  0.268  0.553  1.0
  O  O27  1  0.820  0.548  0.886  1.0
[/CIF]
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The compound described by CaC2O4 crystallizes in the monoclinic P2/m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted edge-sharing CaO7 pentagonal bipyramids. In the second Ca site, Ca(2) is bonded to one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form distorted edge-sharing CaO7 pentagonal bipyramids. There are four inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to two equivalent O(1) atoms. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to two equivalent O(2) atoms. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(4) atom. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted 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 distorted trigonal planar geometry to one Ca(1), one Ca(2), and one C(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one C(3) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Ca(1) and one C(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Ca(2) and one C(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Ca(2) and one C(4) atom. is represented by the CIF file [CIF]
data_Ca(CO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.487
_cell_length_b   6.237
_cell_length_c   9.668
_cell_angle_alpha   89.118
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   451.360
_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  0.500  0.405  0.181  1.0
  Ca  Ca1  1  0.500  0.595  0.819  1.0
  Ca  Ca2  1  0.000  0.586  0.680  1.0
  Ca  Ca3  1  0.000  0.414  0.320  1.0
  C  C4  1  0.895  0.500  0.000  1.0
  C  C5  1  0.395  0.500  0.500  1.0
  C  C6  1  0.500  0.931  0.068  1.0
  C  C7  1  0.105  0.500  0.000  1.0
  C  C8  1  0.605  0.500  0.500  1.0
  C  C9  1  0.000  0.065  0.569  1.0
  C  C10  1  0.500  0.069  0.932  1.0
  C  C11  1  0.000  0.935  0.431  1.0
  O  O12  1  0.180  0.548  0.886  1.0
  O  O13  1  0.180  0.452  0.114  1.0
  O  O14  1  0.820  0.452  0.114  1.0
  O  O15  1  0.680  0.548  0.613  1.0
  O  O16  1  0.500  0.729  0.052  1.0
  O  O17  1  0.320  0.548  0.613  1.0
  O  O18  1  0.500  0.027  0.182  1.0
  O  O19  1  0.000  0.037  0.318  1.0
  O  O20  1  0.320  0.452  0.387  1.0
  O  O21  1  0.680  0.452  0.387  1.0
  O  O22  1  0.000  0.963  0.682  1.0
  O  O23  1  0.500  0.973  0.818  1.0
  O  O24  1  0.500  0.271  0.948  1.0
  O  O25  1  0.000  0.732  0.447  1.0
  O  O26  1  0.000  0.268  0.553  1.0
  O  O27  1  0.820  0.548  0.886  1.0
[/CIF]
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