The material described by Na2YC2HO7 crystallizes in the monoclinic C2/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted octahedral geometry to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(7) atom. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(2), one O(4), one O(6), two equivalent O(3), and two equivalent O(5) atoms. Y(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(6), two equivalent O(1), and two equivalent O(7) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(4) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(3), one O(5), and one O(6) atom. H(1) is bonded in a single-bond geometry to one O(7) atom. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Na(2), and one C(2) atom. In the second O site, O(6) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), one Y(1), and one C(2) atom. In the third O site, O(7) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Y(1), and one H(1) atom. In the fourth O site, O(1) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Y(1), and one C(1) atom. In the fifth O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Y(1), and one C(1) atom. In the sixth O site, O(3) is bonded to two equivalent Na(2), one Y(1), and one C(2) atom to form distorted corner-sharing ONa2YC tetrahedra. In the seventh O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Y(1), and one C(1) atom. is represented by the CIF card [CIF]
data_Na2YHC2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.381
_cell_length_b   9.381
_cell_length_c   11.486
_cell_angle_alpha   84.386
_cell_angle_beta   84.386
_cell_angle_gamma   38.534
_symmetry_Int_Tables_number   1
_cell_volume   626.325
_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
  Na  Na0  1  0.491  0.287  0.382  1.0
  Na  Na1  1  0.713  0.509  0.118  1.0
  Na  Na2  1  0.509  0.713  0.618  1.0
  Na  Na3  1  0.287  0.491  0.882  1.0
  Na  Na4  1  0.176  0.355  0.642  1.0
  Na  Na5  1  0.645  0.824  0.858  1.0
  Na  Na6  1  0.824  0.645  0.358  1.0
  Na  Na7  1  0.355  0.176  0.142  1.0
  Y  Y8  1  0.781  0.098  0.631  1.0
  Y  Y9  1  0.902  0.219  0.869  1.0
  Y  Y10  1  0.219  0.902  0.369  1.0
  Y  Y11  1  0.098  0.781  0.131  1.0
  H  H12  1  0.941  0.261  0.624  1.0
  H  H13  1  0.739  0.059  0.876  1.0
  H  H14  1  0.059  0.739  0.376  1.0
  H  H15  1  0.261  0.941  0.124  1.0
  C  C16  1  0.233  0.638  0.616  1.0
  C  C17  1  0.362  0.767  0.884  1.0
  C  C18  1  0.767  0.362  0.384  1.0
  C  C19  1  0.638  0.233  0.116  1.0
  C  C20  1  0.283  0.134  0.422  1.0
  C  C21  1  0.866  0.717  0.078  1.0
  C  C22  1  0.717  0.866  0.578  1.0
  C  C23  1  0.134  0.283  0.922  1.0
  O  O24  1  0.181  0.806  0.566  1.0
  O  O25  1  0.194  0.819  0.934  1.0
  O  O26  1  0.819  0.194  0.434  1.0
  O  O27  1  0.806  0.181  0.066  1.0
  O  O28  1  0.693  0.095  0.200  1.0
  O  O29  1  0.905  0.307  0.300  1.0
  O  O30  1  0.307  0.905  0.800  1.0
  O  O31  1  0.095  0.693  0.700  1.0
  O  O32  1  0.013  0.384  0.827  1.0
  O  O33  1  0.616  0.987  0.673  1.0
  O  O34  1  0.987  0.616  0.173  1.0
  O  O35  1  0.384  0.013  0.327  1.0
  O  O36  1  0.409  0.431  0.583  1.0
  O  O37  1  0.569  0.591  0.917  1.0
  O  O38  1  0.591  0.569  0.417  1.0
  O  O39  1  0.431  0.409  0.083  1.0
  O  O40  1  0.241  0.298  0.434  1.0
  O  O41  1  0.702  0.759  0.066  1.0
  O  O42  1  0.759  0.702  0.566  1.0
  O  O43  1  0.298  0.241  0.934  1.0
  O  O44  1  0.781  0.919  0.496  1.0
  O  O45  1  0.081  0.219  0.004  1.0
  O  O46  1  0.219  0.081  0.504  1.0
  O  O47  1  0.919  0.781  0.996  1.0
  O  O48  1  0.826  0.298  0.676  1.0
  O  O49  1  0.702  0.174  0.824  1.0
  O  O50  1  0.174  0.702  0.324  1.0
  O  O51  1  0.298  0.826  0.176  1.0
[/CIF]
.
The material described by Na2YC2HO7 crystallizes in the monoclinic C2/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted octahedral geometry to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(7) atom. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(2), one O(4), one O(6), two equivalent O(3), and two equivalent O(5) atoms. Y(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(6), two equivalent O(1), and two equivalent O(7) atoms. There are two inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(4) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(3), one O(5), and one O(6) atom. H(1) is bonded in a single-bond geometry to one O(7) atom. There are seven inequivalent O sites. In the first O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Na(2), and one C(2) atom. In the second O site, O(6) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), one Y(1), and one C(2) atom. In the third O site, O(7) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Y(1), and one H(1) atom. In the fourth O site, O(1) is bonded in a distorted single-bond geometry to one Na(1), two equivalent Y(1), and one C(1) atom. In the fifth O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Y(1), and one C(1) atom. In the sixth O site, O(3) is bonded to two equivalent Na(2), one Y(1), and one C(2) atom to form distorted corner-sharing ONa2YC tetrahedra. In the seventh O site, O(4) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Y(1), and one C(1) atom. is represented by the CIF card [CIF]
data_Na2YHC2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.381
_cell_length_b   9.381
_cell_length_c   11.486
_cell_angle_alpha   84.386
_cell_angle_beta   84.386
_cell_angle_gamma   38.534
_symmetry_Int_Tables_number   1
_cell_volume   626.325
_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
  Na  Na0  1  0.491  0.287  0.382  1.0
  Na  Na1  1  0.713  0.509  0.118  1.0
  Na  Na2  1  0.509  0.713  0.618  1.0
  Na  Na3  1  0.287  0.491  0.882  1.0
  Na  Na4  1  0.176  0.355  0.642  1.0
  Na  Na5  1  0.645  0.824  0.858  1.0
  Na  Na6  1  0.824  0.645  0.358  1.0
  Na  Na7  1  0.355  0.176  0.142  1.0
  Y  Y8  1  0.781  0.098  0.631  1.0
  Y  Y9  1  0.902  0.219  0.869  1.0
  Y  Y10  1  0.219  0.902  0.369  1.0
  Y  Y11  1  0.098  0.781  0.131  1.0
  H  H12  1  0.941  0.261  0.624  1.0
  H  H13  1  0.739  0.059  0.876  1.0
  H  H14  1  0.059  0.739  0.376  1.0
  H  H15  1  0.261  0.941  0.124  1.0
  C  C16  1  0.233  0.638  0.616  1.0
  C  C17  1  0.362  0.767  0.884  1.0
  C  C18  1  0.767  0.362  0.384  1.0
  C  C19  1  0.638  0.233  0.116  1.0
  C  C20  1  0.283  0.134  0.422  1.0
  C  C21  1  0.866  0.717  0.078  1.0
  C  C22  1  0.717  0.866  0.578  1.0
  C  C23  1  0.134  0.283  0.922  1.0
  O  O24  1  0.181  0.806  0.566  1.0
  O  O25  1  0.194  0.819  0.934  1.0
  O  O26  1  0.819  0.194  0.434  1.0
  O  O27  1  0.806  0.181  0.066  1.0
  O  O28  1  0.693  0.095  0.200  1.0
  O  O29  1  0.905  0.307  0.300  1.0
  O  O30  1  0.307  0.905  0.800  1.0
  O  O31  1  0.095  0.693  0.700  1.0
  O  O32  1  0.013  0.384  0.827  1.0
  O  O33  1  0.616  0.987  0.673  1.0
  O  O34  1  0.987  0.616  0.173  1.0
  O  O35  1  0.384  0.013  0.327  1.0
  O  O36  1  0.409  0.431  0.583  1.0
  O  O37  1  0.569  0.591  0.917  1.0
  O  O38  1  0.591  0.569  0.417  1.0
  O  O39  1  0.431  0.409  0.083  1.0
  O  O40  1  0.241  0.298  0.434  1.0
  O  O41  1  0.702  0.759  0.066  1.0
  O  O42  1  0.759  0.702  0.566  1.0
  O  O43  1  0.298  0.241  0.934  1.0
  O  O44  1  0.781  0.919  0.496  1.0
  O  O45  1  0.081  0.219  0.004  1.0
  O  O46  1  0.219  0.081  0.504  1.0
  O  O47  1  0.919  0.781  0.996  1.0
  O  O48  1  0.826  0.298  0.676  1.0
  O  O49  1  0.702  0.174  0.824  1.0
  O  O50  1  0.174  0.702  0.324  1.0
  O  O51  1  0.298  0.826  0.176  1.0
[/CIF]
.