The material described by Ba2C4O9 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 9-coordinate geometry to one O(2), one O(4), one O(5), one O(7), one O(9), two equivalent O(1), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(9), and two equivalent O(6) 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(5) and one O(9) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(6), one O(7), and one O(8) atom. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(2) and one O(4) atom. In the fourth C site, C(4) is bonded in a linear geometry to one O(1) and one O(3) atom. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to two equivalent Ba(1) and one C(4) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(3) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Ba(2) and one C(4) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ba(1), one Ba(2), and one C(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Ba(2) and one C(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Ba(1) and one C(2) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one C(2) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(1) atom. is represented by the CIF card [CIF]
data_Ba2C4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.504
_cell_length_b   9.344
_cell_length_c   9.181
_cell_angle_alpha   66.917
_cell_angle_beta   88.183
_cell_angle_gamma   81.046
_symmetry_Int_Tables_number   1
_cell_volume   506.787
_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  0.259  0.166  0.556  1.0
  Ba  Ba1  1  0.741  0.834  0.444  1.0
  Ba  Ba2  1  0.654  0.512  0.187  1.0
  Ba  Ba3  1  0.346  0.488  0.813  1.0
  C  C4  1  0.285  0.669  0.398  1.0
  C  C5  1  0.715  0.331  0.602  1.0
  C  C6  1  0.558  0.152  0.180  1.0
  C  C7  1  0.442  0.848  0.820  1.0
  C  C8  1  0.154  0.583  0.329  1.0
  C  C9  1  0.846  0.417  0.671  1.0
  C  C10  1  0.015  0.177  0.168  1.0
  C  C11  1  0.985  0.823  0.832  1.0
  O  O12  1  0.023  0.087  0.301  1.0
  O  O13  1  0.977  0.913  0.699  1.0
  O  O14  1  0.254  0.470  0.298  1.0
  O  O15  1  0.746  0.530  0.702  1.0
  O  O16  1  0.015  0.275  0.039  1.0
  O  O17  1  0.985  0.725  0.961  1.0
  O  O18  1  0.041  0.375  0.685  1.0
  O  O19  1  0.959  0.625  0.315  1.0
  O  O20  1  0.528  0.323  0.647  1.0
  O  O21  1  0.472  0.677  0.353  1.0
  O  O22  1  0.524  0.303  0.085  1.0
  O  O23  1  0.476  0.697  0.915  1.0
  O  O24  1  0.687  0.053  0.144  1.0
  O  O25  1  0.313  0.947  0.856  1.0
  O  O26  1  0.466  0.107  0.317  1.0
  O  O27  1  0.534  0.893  0.683  1.0
  O  O28  1  0.202  0.720  0.499  1.0
  O  O29  1  0.798  0.280  0.501  1.0
[/CIF]
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The material described by Ba2C4O9 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 9-coordinate geometry to one O(2), one O(4), one O(5), one O(7), one O(9), two equivalent O(1), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(9), and two equivalent O(6) 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(5) and one O(9) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(6), one O(7), and one O(8) atom. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(2) and one O(4) atom. In the fourth C site, C(4) is bonded in a linear geometry to one O(1) and one O(3) atom. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to two equivalent Ba(1) and one C(4) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(3) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Ba(2) and one C(4) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ba(1), one Ba(2), and one C(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Ba(2) and one C(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Ba(1) and one C(2) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one C(2) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(1) atom. is represented by the CIF card [CIF]
data_Ba2C4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.504
_cell_length_b   9.344
_cell_length_c   9.181
_cell_angle_alpha   66.917
_cell_angle_beta   88.183
_cell_angle_gamma   81.046
_symmetry_Int_Tables_number   1
_cell_volume   506.787
_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  0.259  0.166  0.556  1.0
  Ba  Ba1  1  0.741  0.834  0.444  1.0
  Ba  Ba2  1  0.654  0.512  0.187  1.0
  Ba  Ba3  1  0.346  0.488  0.813  1.0
  C  C4  1  0.285  0.669  0.398  1.0
  C  C5  1  0.715  0.331  0.602  1.0
  C  C6  1  0.558  0.152  0.180  1.0
  C  C7  1  0.442  0.848  0.820  1.0
  C  C8  1  0.154  0.583  0.329  1.0
  C  C9  1  0.846  0.417  0.671  1.0
  C  C10  1  0.015  0.177  0.168  1.0
  C  C11  1  0.985  0.823  0.832  1.0
  O  O12  1  0.023  0.087  0.301  1.0
  O  O13  1  0.977  0.913  0.699  1.0
  O  O14  1  0.254  0.470  0.298  1.0
  O  O15  1  0.746  0.530  0.702  1.0
  O  O16  1  0.015  0.275  0.039  1.0
  O  O17  1  0.985  0.725  0.961  1.0
  O  O18  1  0.041  0.375  0.685  1.0
  O  O19  1  0.959  0.625  0.315  1.0
  O  O20  1  0.528  0.323  0.647  1.0
  O  O21  1  0.472  0.677  0.353  1.0
  O  O22  1  0.524  0.303  0.085  1.0
  O  O23  1  0.476  0.697  0.915  1.0
  O  O24  1  0.687  0.053  0.144  1.0
  O  O25  1  0.313  0.947  0.856  1.0
  O  O26  1  0.466  0.107  0.317  1.0
  O  O27  1  0.534  0.893  0.683  1.0
  O  O28  1  0.202  0.720  0.499  1.0
  O  O29  1  0.798  0.280  0.501  1.0
[/CIF]
.