The crystal structure described by Fe2C2O7 crystallizes in the monoclinic C2 space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(4), one O(5), one O(7), and one O(9) atom to form corner-sharing FeO4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(10), one O(3), one O(5), and one O(6) atom to form corner-sharing FeO4 tetrahedra. In the third Fe site, Fe(3) is bonded to one O(1), one O(11), one O(2), and one O(8) atom to form corner-sharing FeO4 tetrahedra. There are three inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(3), one O(8), and one O(9) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(2), one O(4), and one O(6) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(10), one O(11), and one O(7) atom. There are eleven inequivalent O sites. In the first O site, O(6) is bonded in a bent 120 degrees geometry to one Fe(2) and one C(2) atom. In the second O site, O(7) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(3) atom. In the third O site, O(8) is bonded in a bent 120 degrees geometry to one Fe(3) and one C(1) atom. In the fourth O site, O(9) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(1) atom. In the fifth O site, O(10) is bonded in a bent 120 degrees geometry to one Fe(2) and one C(3) atom. In the sixth O site, O(11) is bonded in a bent 120 degrees geometry to one Fe(3) and one C(3) atom. In the seventh O site, O(1) is bonded in a linear geometry to two equivalent Fe(3) atoms. In the eighth O site, O(2) is bonded in a bent 120 degrees geometry to one Fe(3) and one C(2) atom. In the ninth O site, O(3) is bonded in a bent 120 degrees geometry to one Fe(2) and one C(1) atom. In the tenth O site, O(4) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(2) atom. In the eleventh O site, O(5) is bonded in a linear geometry to one Fe(1) and one Fe(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe2C2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.530
_cell_length_b   8.530
_cell_length_c   8.384
_cell_angle_alpha   89.415
_cell_angle_beta   89.415
_cell_angle_gamma   60.230
_symmetry_Int_Tables_number   1
_cell_volume   529.470
_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
  Fe  Fe0  1  0.668  0.666  0.822  1.0
  Fe  Fe1  1  0.334  0.332  0.178  1.0
  Fe  Fe2  1  0.666  0.666  0.256  1.0
  Fe  Fe3  1  0.334  0.334  0.744  1.0
  Fe  Fe4  1  1.000  0.002  0.285  1.0
  Fe  Fe5  1  0.998  0.000  0.715  1.0
  C  C6  1  0.002  0.339  0.274  1.0
  C  C7  1  0.661  0.998  0.726  1.0
  C  C8  1  0.664  0.000  0.268  1.0
  C  C9  1  1.000  0.336  0.732  1.0
  C  C10  1  0.333  0.664  0.266  1.0
  C  C11  1  0.336  0.667  0.734  1.0
  O  O12  1  1.000  0.000  0.500  1.0
  O  O13  1  0.932  0.241  0.787  1.0
  O  O14  1  0.759  0.068  0.213  1.0
  O  O15  1  0.837  0.425  0.329  1.0
  O  O16  1  0.575  0.163  0.671  1.0
  O  O17  1  0.905  0.510  0.732  1.0
  O  O18  1  0.490  0.095  0.268  1.0
  O  O19  1  0.669  0.670  0.038  1.0
  O  O20  1  0.330  0.331  0.962  1.0
  O  O21  1  0.164  0.259  0.676  1.0
  O  O22  1  0.741  0.836  0.324  1.0
  O  O23  1  0.510  0.586  0.736  1.0
  O  O24  1  0.414  0.490  0.264  1.0
  O  O25  1  0.822  0.932  0.783  1.0
  O  O26  1  0.068  0.178  0.217  1.0
  O  O27  1  0.583  0.901  0.724  1.0
  O  O28  1  0.099  0.417  0.276  1.0
  O  O29  1  0.419  0.743  0.318  1.0
  O  O30  1  0.257  0.581  0.682  1.0
  O  O31  1  0.241  0.831  0.784  1.0
  O  O32  1  0.169  0.759  0.216  1.0
[/CIF]
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The crystal structure described by Fe2C2O7 crystallizes in the monoclinic C2 space group. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(4), one O(5), one O(7), and one O(9) atom to form corner-sharing FeO4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(10), one O(3), one O(5), and one O(6) atom to form corner-sharing FeO4 tetrahedra. In the third Fe site, Fe(3) is bonded to one O(1), one O(11), one O(2), and one O(8) atom to form corner-sharing FeO4 tetrahedra. There are three inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(3), one O(8), and one O(9) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(2), one O(4), and one O(6) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(10), one O(11), and one O(7) atom. There are eleven inequivalent O sites. In the first O site, O(6) is bonded in a bent 120 degrees geometry to one Fe(2) and one C(2) atom. In the second O site, O(7) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(3) atom. In the third O site, O(8) is bonded in a bent 120 degrees geometry to one Fe(3) and one C(1) atom. In the fourth O site, O(9) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(1) atom. In the fifth O site, O(10) is bonded in a bent 120 degrees geometry to one Fe(2) and one C(3) atom. In the sixth O site, O(11) is bonded in a bent 120 degrees geometry to one Fe(3) and one C(3) atom. In the seventh O site, O(1) is bonded in a linear geometry to two equivalent Fe(3) atoms. In the eighth O site, O(2) is bonded in a bent 120 degrees geometry to one Fe(3) and one C(2) atom. In the ninth O site, O(3) is bonded in a bent 120 degrees geometry to one Fe(2) and one C(1) atom. In the tenth O site, O(4) is bonded in a bent 120 degrees geometry to one Fe(1) and one C(2) atom. In the eleventh O site, O(5) is bonded in a linear geometry to one Fe(1) and one Fe(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe2C2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.530
_cell_length_b   8.530
_cell_length_c   8.384
_cell_angle_alpha   89.415
_cell_angle_beta   89.415
_cell_angle_gamma   60.230
_symmetry_Int_Tables_number   1
_cell_volume   529.470
_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
  Fe  Fe0  1  0.668  0.666  0.822  1.0
  Fe  Fe1  1  0.334  0.332  0.178  1.0
  Fe  Fe2  1  0.666  0.666  0.256  1.0
  Fe  Fe3  1  0.334  0.334  0.744  1.0
  Fe  Fe4  1  1.000  0.002  0.285  1.0
  Fe  Fe5  1  0.998  0.000  0.715  1.0
  C  C6  1  0.002  0.339  0.274  1.0
  C  C7  1  0.661  0.998  0.726  1.0
  C  C8  1  0.664  0.000  0.268  1.0
  C  C9  1  1.000  0.336  0.732  1.0
  C  C10  1  0.333  0.664  0.266  1.0
  C  C11  1  0.336  0.667  0.734  1.0
  O  O12  1  1.000  0.000  0.500  1.0
  O  O13  1  0.932  0.241  0.787  1.0
  O  O14  1  0.759  0.068  0.213  1.0
  O  O15  1  0.837  0.425  0.329  1.0
  O  O16  1  0.575  0.163  0.671  1.0
  O  O17  1  0.905  0.510  0.732  1.0
  O  O18  1  0.490  0.095  0.268  1.0
  O  O19  1  0.669  0.670  0.038  1.0
  O  O20  1  0.330  0.331  0.962  1.0
  O  O21  1  0.164  0.259  0.676  1.0
  O  O22  1  0.741  0.836  0.324  1.0
  O  O23  1  0.510  0.586  0.736  1.0
  O  O24  1  0.414  0.490  0.264  1.0
  O  O25  1  0.822  0.932  0.783  1.0
  O  O26  1  0.068  0.178  0.217  1.0
  O  O27  1  0.583  0.901  0.724  1.0
  O  O28  1  0.099  0.417  0.276  1.0
  O  O29  1  0.419  0.743  0.318  1.0
  O  O30  1  0.257  0.581  0.682  1.0
  O  O31  1  0.241  0.831  0.784  1.0
  O  O32  1  0.169  0.759  0.216  1.0
[/CIF]
.