The crystal structure described by Mg2Cu2CH2O9 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted edge-sharing MgO5 square pyramids. Cu(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), and two equivalent O(5) atoms. C(1) is bonded in a trigonal planar geometry to one O(4) and two equivalent O(3) atoms. H(1) is bonded in a distorted linear geometry to one O(2) and one O(4) atom. There are five inequivalent O sites. In the first O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), one Cu(1), and one H(1) atom. In the second O site, O(3) is bonded in a bent 120 degrees geometry to one Mg(1) and one C(1) atom. In the third O site, O(4) is bonded in a 3-coordinate geometry to one C(1) and two equivalent H(1) atoms. In the fourth O site, O(5) is bonded in a water-like geometry to two equivalent Cu(1) atoms. In the fifth O site, O(1) is bonded in a trigonal non-coplanar geometry to two equivalent Mg(1) and one Cu(1) atom. is represented by the CIF file [CIF]
data_Mg2Cu2H2CO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.974
_cell_length_b   7.974
_cell_length_c   7.705
_cell_angle_alpha   73.716
_cell_angle_beta   73.716
_cell_angle_gamma   88.114
_symmetry_Int_Tables_number   1
_cell_volume   450.889
_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  0.317  0.964  0.663  1.0
  Mg  Mg1  1  0.683  0.036  0.337  1.0
  Mg  Mg2  1  0.036  0.683  0.837  1.0
  Mg  Mg3  1  0.964  0.317  0.163  1.0
  Cu  Cu4  1  0.445  0.658  0.532  1.0
  Cu  Cu5  1  0.555  0.342  0.468  1.0
  Cu  Cu6  1  0.342  0.555  0.968  1.0
  Cu  Cu7  1  0.658  0.445  0.032  1.0
  H  H8  1  0.797  0.212  0.550  1.0
  H  H9  1  0.203  0.788  0.450  1.0
  H  H10  1  0.788  0.203  0.950  1.0
  H  H11  1  0.212  0.797  0.050  1.0
  C  C12  1  0.948  0.052  0.750  1.0
  C  C13  1  0.052  0.948  0.250  1.0
  O  O14  1  0.545  0.849  0.561  1.0
  O  O15  1  0.455  0.151  0.439  1.0
  O  O16  1  0.151  0.455  0.939  1.0
  O  O17  1  0.849  0.545  0.061  1.0
  O  O18  1  0.228  0.766  0.576  1.0
  O  O19  1  0.772  0.234  0.424  1.0
  O  O20  1  0.234  0.772  0.924  1.0
  O  O21  1  0.766  0.228  0.076  1.0
  O  O22  1  0.103  0.095  0.745  1.0
  O  O23  1  0.897  0.905  0.255  1.0
  O  O24  1  0.905  0.897  0.755  1.0
  O  O25  1  0.095  0.103  0.245  1.0
  O  O26  1  0.831  0.169  0.750  1.0
  O  O27  1  0.169  0.831  0.250  1.0
  O  O28  1  0.536  0.641  0.998  1.0
  O  O29  1  0.464  0.359  0.002  1.0
  O  O30  1  0.359  0.464  0.502  1.0
  O  O31  1  0.641  0.536  0.498  1.0
[/CIF]
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The crystal structure described by Mg2Cu2CH2O9 crystallizes in the monoclinic C2/c space group. Mg(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted edge-sharing MgO5 square pyramids. Cu(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), and two equivalent O(5) atoms. C(1) is bonded in a trigonal planar geometry to one O(4) and two equivalent O(3) atoms. H(1) is bonded in a distorted linear geometry to one O(2) and one O(4) atom. There are five inequivalent O sites. In the first O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1), one Cu(1), and one H(1) atom. In the second O site, O(3) is bonded in a bent 120 degrees geometry to one Mg(1) and one C(1) atom. In the third O site, O(4) is bonded in a 3-coordinate geometry to one C(1) and two equivalent H(1) atoms. In the fourth O site, O(5) is bonded in a water-like geometry to two equivalent Cu(1) atoms. In the fifth O site, O(1) is bonded in a trigonal non-coplanar geometry to two equivalent Mg(1) and one Cu(1) atom. is represented by the CIF file [CIF]
data_Mg2Cu2H2CO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.974
_cell_length_b   7.974
_cell_length_c   7.705
_cell_angle_alpha   73.716
_cell_angle_beta   73.716
_cell_angle_gamma   88.114
_symmetry_Int_Tables_number   1
_cell_volume   450.889
_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  0.317  0.964  0.663  1.0
  Mg  Mg1  1  0.683  0.036  0.337  1.0
  Mg  Mg2  1  0.036  0.683  0.837  1.0
  Mg  Mg3  1  0.964  0.317  0.163  1.0
  Cu  Cu4  1  0.445  0.658  0.532  1.0
  Cu  Cu5  1  0.555  0.342  0.468  1.0
  Cu  Cu6  1  0.342  0.555  0.968  1.0
  Cu  Cu7  1  0.658  0.445  0.032  1.0
  H  H8  1  0.797  0.212  0.550  1.0
  H  H9  1  0.203  0.788  0.450  1.0
  H  H10  1  0.788  0.203  0.950  1.0
  H  H11  1  0.212  0.797  0.050  1.0
  C  C12  1  0.948  0.052  0.750  1.0
  C  C13  1  0.052  0.948  0.250  1.0
  O  O14  1  0.545  0.849  0.561  1.0
  O  O15  1  0.455  0.151  0.439  1.0
  O  O16  1  0.151  0.455  0.939  1.0
  O  O17  1  0.849  0.545  0.061  1.0
  O  O18  1  0.228  0.766  0.576  1.0
  O  O19  1  0.772  0.234  0.424  1.0
  O  O20  1  0.234  0.772  0.924  1.0
  O  O21  1  0.766  0.228  0.076  1.0
  O  O22  1  0.103  0.095  0.745  1.0
  O  O23  1  0.897  0.905  0.255  1.0
  O  O24  1  0.905  0.897  0.755  1.0
  O  O25  1  0.095  0.103  0.245  1.0
  O  O26  1  0.831  0.169  0.750  1.0
  O  O27  1  0.169  0.831  0.250  1.0
  O  O28  1  0.536  0.641  0.998  1.0
  O  O29  1  0.464  0.359  0.002  1.0
  O  O30  1  0.359  0.464  0.502  1.0
  O  O31  1  0.641  0.536  0.498  1.0
[/CIF]
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