The material structure 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 in a 7-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one C(4), one O(6), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. There are four inequivalent C sites. In the first C site, C(1) is bonded in a bent 120 degrees geometry to one O(1) and one O(3) atom. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to two equivalent O(4) atoms. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to two equivalent O(2) atoms. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to one Ca(2) and one O(5) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted L-shaped geometry to one Ca(1) 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(3) 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. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ca(1), one Ca(2), and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Ca(2), one C(4), and one O(6) atom. In the sixth O site, O(6) is bonded in a distorted L-shaped geometry to one Ca(2) and one O(5) atom. is represented by the CIF card [CIF]
data_Ca(CO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.351
_cell_length_b   6.199
_cell_length_c   9.868
_cell_angle_alpha   72.588
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   429.096
_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  0.000  0.399  0.699  1.0
  Ca  Ca1  1  0.500  0.519  0.191  1.0
  Ca  Ca2  1  0.000  0.601  0.301  1.0
  Ca  Ca3  1  0.500  0.481  0.809  1.0
  C  C4  1  0.000  0.923  0.451  1.0
  C  C5  1  0.893  0.500  0.000  1.0
  C  C6  1  0.606  0.500  0.500  1.0
  C  C7  1  0.394  0.500  0.500  1.0
  C  C8  1  0.500  0.012  0.929  1.0
  C  C9  1  0.107  0.500  0.000  1.0
  C  C10  1  0.000  0.077  0.549  1.0
  C  C11  1  0.500  0.988  0.071  1.0
  O  O12  1  0.000  0.005  0.318  1.0
  O  O13  1  0.683  0.543  0.380  1.0
  O  O14  1  0.000  0.288  0.486  1.0
  O  O15  1  0.317  0.457  0.620  1.0
  O  O16  1  0.683  0.457  0.620  1.0
  O  O17  1  0.815  0.548  0.102  1.0
  O  O18  1  0.000  0.995  0.682  1.0
  O  O19  1  0.500  0.829  0.886  1.0
  O  O20  1  0.185  0.452  0.898  1.0
  O  O21  1  0.815  0.452  0.898  1.0
  O  O22  1  0.500  0.869  0.734  1.0
  O  O23  1  0.317  0.543  0.380  1.0
  O  O24  1  0.500  0.171  0.114  1.0
  O  O25  1  0.185  0.548  0.102  1.0
  O  O26  1  0.500  0.131  0.266  1.0
  O  O27  1  0.000  0.712  0.514  1.0
[/CIF]
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The material structure 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 in a 7-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one C(4), one O(6), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. There are four inequivalent C sites. In the first C site, C(1) is bonded in a bent 120 degrees geometry to one O(1) and one O(3) atom. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to two equivalent O(4) atoms. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to two equivalent O(2) atoms. In the fourth C site, C(4) is bonded in a distorted single-bond geometry to one Ca(2) and one O(5) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted L-shaped geometry to one Ca(1) 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(3) 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. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ca(1), one Ca(2), and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Ca(2), one C(4), and one O(6) atom. In the sixth O site, O(6) is bonded in a distorted L-shaped geometry to one Ca(2) and one O(5) atom. is represented by the CIF card [CIF]
data_Ca(CO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.351
_cell_length_b   6.199
_cell_length_c   9.868
_cell_angle_alpha   72.588
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   429.096
_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  0.000  0.399  0.699  1.0
  Ca  Ca1  1  0.500  0.519  0.191  1.0
  Ca  Ca2  1  0.000  0.601  0.301  1.0
  Ca  Ca3  1  0.500  0.481  0.809  1.0
  C  C4  1  0.000  0.923  0.451  1.0
  C  C5  1  0.893  0.500  0.000  1.0
  C  C6  1  0.606  0.500  0.500  1.0
  C  C7  1  0.394  0.500  0.500  1.0
  C  C8  1  0.500  0.012  0.929  1.0
  C  C9  1  0.107  0.500  0.000  1.0
  C  C10  1  0.000  0.077  0.549  1.0
  C  C11  1  0.500  0.988  0.071  1.0
  O  O12  1  0.000  0.005  0.318  1.0
  O  O13  1  0.683  0.543  0.380  1.0
  O  O14  1  0.000  0.288  0.486  1.0
  O  O15  1  0.317  0.457  0.620  1.0
  O  O16  1  0.683  0.457  0.620  1.0
  O  O17  1  0.815  0.548  0.102  1.0
  O  O18  1  0.000  0.995  0.682  1.0
  O  O19  1  0.500  0.829  0.886  1.0
  O  O20  1  0.185  0.452  0.898  1.0
  O  O21  1  0.815  0.452  0.898  1.0
  O  O22  1  0.500  0.869  0.734  1.0
  O  O23  1  0.317  0.543  0.380  1.0
  O  O24  1  0.500  0.171  0.114  1.0
  O  O25  1  0.185  0.548  0.102  1.0
  O  O26  1  0.500  0.131  0.266  1.0
  O  O27  1  0.000  0.712  0.514  1.0
[/CIF]
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