The structure described by K4C2O9 crystallizes in the monoclinic C2/c space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(5), and four equivalent O(3) atoms. In the third K site, K(3) is bonded in a 8-coordinate geometry to one O(2), one O(3), two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(5) atom. There are five inequivalent O sites. In the first O site, O(3) is bonded to one K(1), one K(3), and two equivalent K(2) atoms to form a mixture of distorted corner and edge-sharing OK4 trigonal pyramids. In the second O site, O(4) is bonded to four equivalent K(3) atoms to form a mixture of distorted corner and edge-sharing OK4 trigonal pyramids. In the third O site, O(5) is bonded in a distorted single-bond geometry to one K(1), one K(2), two equivalent K(3), and one C(1) atom. In the fourth O site, O(1) is bonded in a distorted single-bond geometry to one K(1), one K(2), two equivalent K(3), and one C(1) atom. In the fifth O site, O(2) is bonded in a single-bond geometry to one K(1), one K(3), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K4C2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.727
_cell_length_b   8.727
_cell_length_c   7.250
_cell_angle_alpha   69.760
_cell_angle_beta   69.760
_cell_angle_gamma   93.364
_symmetry_Int_Tables_number   1
_cell_volume   475.959
_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
  K  K0  1  0.177  0.823  0.250  1.0
  K  K1  1  0.823  0.177  0.750  1.0
  K  K2  1  0.890  0.110  0.250  1.0
  K  K3  1  0.110  0.890  0.750  1.0
  K  K4  1  0.532  0.761  0.438  1.0
  K  K5  1  0.468  0.239  0.562  1.0
  K  K6  1  0.239  0.468  0.062  1.0
  K  K7  1  0.761  0.532  0.938  1.0
  C  C8  1  0.473  0.142  0.152  1.0
  C  C9  1  0.527  0.858  0.848  1.0
  C  C10  1  0.858  0.527  0.348  1.0
  C  C11  1  0.142  0.473  0.652  1.0
  O  O12  1  0.352  0.054  0.334  1.0
  O  O13  1  0.648  0.946  0.666  1.0
  O  O14  1  0.946  0.648  0.166  1.0
  O  O15  1  0.054  0.352  0.834  1.0
  O  O16  1  0.552  0.816  0.025  1.0
  O  O17  1  0.448  0.184  0.975  1.0
  O  O18  1  0.184  0.448  0.475  1.0
  O  O19  1  0.816  0.552  0.525  1.0
  O  O20  1  0.821  0.888  0.076  1.0
  O  O21  1  0.179  0.112  0.924  1.0
  O  O22  1  0.112  0.179  0.424  1.0
  O  O23  1  0.888  0.821  0.576  1.0
  O  O24  1  0.466  0.534  0.250  1.0
  O  O25  1  0.534  0.466  0.750  1.0
  O  O26  1  0.620  0.182  0.143  1.0
  O  O27  1  0.380  0.818  0.857  1.0
  O  O28  1  0.818  0.380  0.357  1.0
  O  O29  1  0.182  0.620  0.643  1.0
[/CIF]
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The structure described by K4C2O9 crystallizes in the monoclinic C2/c space group. There are three inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(5), and four equivalent O(3) atoms. In the third K site, K(3) is bonded in a 8-coordinate geometry to one O(2), one O(3), two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(5) atom. There are five inequivalent O sites. In the first O site, O(3) is bonded to one K(1), one K(3), and two equivalent K(2) atoms to form a mixture of distorted corner and edge-sharing OK4 trigonal pyramids. In the second O site, O(4) is bonded to four equivalent K(3) atoms to form a mixture of distorted corner and edge-sharing OK4 trigonal pyramids. In the third O site, O(5) is bonded in a distorted single-bond geometry to one K(1), one K(2), two equivalent K(3), and one C(1) atom. In the fourth O site, O(1) is bonded in a distorted single-bond geometry to one K(1), one K(2), two equivalent K(3), and one C(1) atom. In the fifth O site, O(2) is bonded in a single-bond geometry to one K(1), one K(3), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K4C2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.727
_cell_length_b   8.727
_cell_length_c   7.250
_cell_angle_alpha   69.760
_cell_angle_beta   69.760
_cell_angle_gamma   93.364
_symmetry_Int_Tables_number   1
_cell_volume   475.959
_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
  K  K0  1  0.177  0.823  0.250  1.0
  K  K1  1  0.823  0.177  0.750  1.0
  K  K2  1  0.890  0.110  0.250  1.0
  K  K3  1  0.110  0.890  0.750  1.0
  K  K4  1  0.532  0.761  0.438  1.0
  K  K5  1  0.468  0.239  0.562  1.0
  K  K6  1  0.239  0.468  0.062  1.0
  K  K7  1  0.761  0.532  0.938  1.0
  C  C8  1  0.473  0.142  0.152  1.0
  C  C9  1  0.527  0.858  0.848  1.0
  C  C10  1  0.858  0.527  0.348  1.0
  C  C11  1  0.142  0.473  0.652  1.0
  O  O12  1  0.352  0.054  0.334  1.0
  O  O13  1  0.648  0.946  0.666  1.0
  O  O14  1  0.946  0.648  0.166  1.0
  O  O15  1  0.054  0.352  0.834  1.0
  O  O16  1  0.552  0.816  0.025  1.0
  O  O17  1  0.448  0.184  0.975  1.0
  O  O18  1  0.184  0.448  0.475  1.0
  O  O19  1  0.816  0.552  0.525  1.0
  O  O20  1  0.821  0.888  0.076  1.0
  O  O21  1  0.179  0.112  0.924  1.0
  O  O22  1  0.112  0.179  0.424  1.0
  O  O23  1  0.888  0.821  0.576  1.0
  O  O24  1  0.466  0.534  0.250  1.0
  O  O25  1  0.534  0.466  0.750  1.0
  O  O26  1  0.620  0.182  0.143  1.0
  O  O27  1  0.380  0.818  0.857  1.0
  O  O28  1  0.818  0.380  0.357  1.0
  O  O29  1  0.182  0.620  0.643  1.0
[/CIF]
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