The material structure described by Mg3O(CO3)2 crystallizes in the tetragonal I-42m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form MgO5 trigonal bipyramids that share corners with three equivalent Mg(1)O5 trigonal bipyramids and edges with two equivalent Mg(2)O6 octahedra. In the second Mg site, Mg(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra and edges with four equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedra are not tilted. C(1) is bonded in a trigonal planar geometry to one O(2) and two equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(3) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Mg(2) atoms. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(2), and one C(1) atom. In the third O site, O(2) is bonded in a trigonal planar geometry to two equivalent Mg(1) and one C(1) atom. is represented by the CIF file [CIF]
data_Mg3C2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.511
_cell_length_b   7.511
_cell_length_c   7.511
_cell_angle_alpha   107.095
_cell_angle_beta   107.095
_cell_angle_gamma   114.336
_symmetry_Int_Tables_number   1
_cell_volume   324.388
_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
  Mg  Mg0  1  0.783  0.500  0.283  1.0
  Mg  Mg1  1  0.500  0.217  0.717  1.0
  Mg  Mg2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.500  0.783  0.283  1.0
  Mg  Mg4  1  0.217  0.500  0.717  1.0
  Mg  Mg5  1  0.750  0.250  0.500  1.0
  C  C6  1  0.459  0.459  0.478  1.0
  C  C7  1  0.981  0.981  0.522  1.0
  C  C8  1  0.541  0.019  0.000  1.0
  C  C9  1  0.019  0.541  0.000  1.0
  O  O10  1  0.388  0.566  0.406  1.0
  O  O11  1  0.566  0.388  0.406  1.0
  O  O12  1  0.420  0.420  0.627  1.0
  O  O13  1  0.160  0.982  0.594  1.0
  O  O14  1  0.982  0.160  0.594  1.0
  O  O15  1  0.792  0.792  0.373  1.0
  O  O16  1  0.612  0.018  0.178  1.0
  O  O17  1  0.434  0.840  0.822  1.0
  O  O18  1  0.580  0.208  0.000  1.0
  O  O19  1  0.840  0.434  0.822  1.0
  O  O20  1  0.018  0.612  0.178  1.0
  O  O21  1  0.208  0.580  0.000  1.0
  O  O22  1  0.500  0.000  0.500  1.0
  O  O23  1  0.000  0.500  0.500  1.0
[/CIF]
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The material structure described by Mg3O(CO3)2 crystallizes in the tetragonal I-42m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form MgO5 trigonal bipyramids that share corners with three equivalent Mg(1)O5 trigonal bipyramids and edges with two equivalent Mg(2)O6 octahedra. In the second Mg site, Mg(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with two equivalent Mg(2)O6 octahedra and edges with four equivalent Mg(1)O5 trigonal bipyramids. The corner-sharing octahedra are not tilted. C(1) is bonded in a trigonal planar geometry to one O(2) and two equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(3) is bonded in a square co-planar geometry to two equivalent Mg(1) and two equivalent Mg(2) atoms. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(2), and one C(1) atom. In the third O site, O(2) is bonded in a trigonal planar geometry to two equivalent Mg(1) and one C(1) atom. is represented by the CIF file [CIF]
data_Mg3C2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.511
_cell_length_b   7.511
_cell_length_c   7.511
_cell_angle_alpha   107.095
_cell_angle_beta   107.095
_cell_angle_gamma   114.336
_symmetry_Int_Tables_number   1
_cell_volume   324.388
_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
  Mg  Mg0  1  0.783  0.500  0.283  1.0
  Mg  Mg1  1  0.500  0.217  0.717  1.0
  Mg  Mg2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.500  0.783  0.283  1.0
  Mg  Mg4  1  0.217  0.500  0.717  1.0
  Mg  Mg5  1  0.750  0.250  0.500  1.0
  C  C6  1  0.459  0.459  0.478  1.0
  C  C7  1  0.981  0.981  0.522  1.0
  C  C8  1  0.541  0.019  0.000  1.0
  C  C9  1  0.019  0.541  0.000  1.0
  O  O10  1  0.388  0.566  0.406  1.0
  O  O11  1  0.566  0.388  0.406  1.0
  O  O12  1  0.420  0.420  0.627  1.0
  O  O13  1  0.160  0.982  0.594  1.0
  O  O14  1  0.982  0.160  0.594  1.0
  O  O15  1  0.792  0.792  0.373  1.0
  O  O16  1  0.612  0.018  0.178  1.0
  O  O17  1  0.434  0.840  0.822  1.0
  O  O18  1  0.580  0.208  0.000  1.0
  O  O19  1  0.840  0.434  0.822  1.0
  O  O20  1  0.018  0.612  0.178  1.0
  O  O21  1  0.208  0.580  0.000  1.0
  O  O22  1  0.500  0.000  0.500  1.0
  O  O23  1  0.000  0.500  0.500  1.0
[/CIF]
.