The material structure described by Ba2C4H2O9 crystallizes in the triclinic P-1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one O(4), one O(5), one O(6), one O(7), one O(8), one O(9), and two equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(3), one O(4), one O(5), one O(8), one O(9), two equivalent O(2), and two equivalent O(7) atoms. There are four inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(2) and one O(6) atom. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(4) and one O(9) atom. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(8) atom. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(7) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(3) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(3) atom. There are nine inequivalent O sites. In the first O site, O(9) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(2) atom. In the second O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one C(4) atom. In the third O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one C(1) atom. In the fourth O site, O(3) is bonded in a water-like geometry to one Ba(2), one H(1), and one H(2) atom. In the fifth O site, O(4) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(2) atom. In the sixth O site, O(5) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(3) atom. In the seventh O site, O(6) is bonded in a single-bond geometry to one Ba(1) and one C(1) atom. In the eighth O site, O(7) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one C(4) atom. In the ninth O site, O(8) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(3) atom. is represented by the CIF file [CIF]
data_Ba2H2C4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.473
_cell_length_b   8.694
_cell_length_c   9.770
_cell_angle_alpha   65.077
_cell_angle_beta   83.745
_cell_angle_gamma   82.034
_symmetry_Int_Tables_number   1
_cell_volume   493.038
_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
  Ba  Ba0  1  0.751  0.491  0.204  1.0
  Ba  Ba1  1  0.249  0.509  0.796  1.0
  Ba  Ba2  1  0.194  0.134  0.578  1.0
  Ba  Ba3  1  0.806  0.866  0.422  1.0
  H  H4  1  0.140  0.041  0.968  1.0
  H  H5  1  0.860  0.959  0.032  1.0
  H  H6  1  0.718  0.102  0.071  1.0
  H  H7  1  0.282  0.898  0.929  1.0
  C  C8  1  0.392  0.184  0.188  1.0
  C  C9  1  0.608  0.816  0.812  1.0
  C  C10  1  0.232  0.586  0.319  1.0
  C  C11  1  0.768  0.414  0.681  1.0
  C  C12  1  0.348  0.676  0.392  1.0
  C  C13  1  0.652  0.324  0.608  1.0
  C  C14  1  0.149  0.223  0.193  1.0
  C  C15  1  0.851  0.777  0.807  1.0
  O  O16  1  0.067  0.323  0.071  1.0
  O  O17  1  0.933  0.677  0.929  1.0
  O  O18  1  0.477  0.112  0.314  1.0
  O  O19  1  0.523  0.888  0.686  1.0
  O  O20  1  0.836  0.009  0.106  1.0
  O  O21  1  0.164  0.991  0.894  1.0
  O  O22  1  0.964  0.376  0.691  1.0
  O  O23  1  0.036  0.624  0.309  1.0
  O  O24  1  0.457  0.313  0.643  1.0
  O  O25  1  0.543  0.687  0.357  1.0
  O  O26  1  0.484  0.233  0.058  1.0
  O  O27  1  0.516  0.767  0.942  1.0
  O  O28  1  0.046  0.158  0.319  1.0
  O  O29  1  0.954  0.842  0.681  1.0
  O  O30  1  0.241  0.728  0.485  1.0
  O  O31  1  0.759  0.272  0.515  1.0
  O  O32  1  0.340  0.476  0.281  1.0
  O  O33  1  0.660  0.524  0.719  1.0
[/CIF]
.
The material structure described by Ba2C4H2O9 crystallizes in the triclinic P-1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one O(4), one O(5), one O(6), one O(7), one O(8), one O(9), and two equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(3), one O(4), one O(5), one O(8), one O(9), two equivalent O(2), and two equivalent O(7) atoms. There are four inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(2) and one O(6) atom. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(4) and one O(9) atom. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(8) atom. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(7) atom. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(3) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(3) atom. There are nine inequivalent O sites. In the first O site, O(9) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(2) atom. In the second O site, O(1) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one C(4) atom. In the third O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one C(1) atom. In the fourth O site, O(3) is bonded in a water-like geometry to one Ba(2), one H(1), and one H(2) atom. In the fifth O site, O(4) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(2) atom. In the sixth O site, O(5) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(3) atom. In the seventh O site, O(6) is bonded in a single-bond geometry to one Ba(1) and one C(1) atom. In the eighth O site, O(7) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one C(4) atom. In the ninth O site, O(8) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(3) atom. is represented by the CIF file [CIF]
data_Ba2H2C4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.473
_cell_length_b   8.694
_cell_length_c   9.770
_cell_angle_alpha   65.077
_cell_angle_beta   83.745
_cell_angle_gamma   82.034
_symmetry_Int_Tables_number   1
_cell_volume   493.038
_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
  Ba  Ba0  1  0.751  0.491  0.204  1.0
  Ba  Ba1  1  0.249  0.509  0.796  1.0
  Ba  Ba2  1  0.194  0.134  0.578  1.0
  Ba  Ba3  1  0.806  0.866  0.422  1.0
  H  H4  1  0.140  0.041  0.968  1.0
  H  H5  1  0.860  0.959  0.032  1.0
  H  H6  1  0.718  0.102  0.071  1.0
  H  H7  1  0.282  0.898  0.929  1.0
  C  C8  1  0.392  0.184  0.188  1.0
  C  C9  1  0.608  0.816  0.812  1.0
  C  C10  1  0.232  0.586  0.319  1.0
  C  C11  1  0.768  0.414  0.681  1.0
  C  C12  1  0.348  0.676  0.392  1.0
  C  C13  1  0.652  0.324  0.608  1.0
  C  C14  1  0.149  0.223  0.193  1.0
  C  C15  1  0.851  0.777  0.807  1.0
  O  O16  1  0.067  0.323  0.071  1.0
  O  O17  1  0.933  0.677  0.929  1.0
  O  O18  1  0.477  0.112  0.314  1.0
  O  O19  1  0.523  0.888  0.686  1.0
  O  O20  1  0.836  0.009  0.106  1.0
  O  O21  1  0.164  0.991  0.894  1.0
  O  O22  1  0.964  0.376  0.691  1.0
  O  O23  1  0.036  0.624  0.309  1.0
  O  O24  1  0.457  0.313  0.643  1.0
  O  O25  1  0.543  0.687  0.357  1.0
  O  O26  1  0.484  0.233  0.058  1.0
  O  O27  1  0.516  0.767  0.942  1.0
  O  O28  1  0.046  0.158  0.319  1.0
  O  O29  1  0.954  0.842  0.681  1.0
  O  O30  1  0.241  0.728  0.485  1.0
  O  O31  1  0.759  0.272  0.515  1.0
  O  O32  1  0.340  0.476  0.281  1.0
  O  O33  1  0.660  0.524  0.719  1.0
[/CIF]
.