The crystal structure described by BaC2O4 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(1), one O(3), one O(4), one O(5), one O(7), two equivalent O(2), and two equivalent O(6) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one O(1), one O(4), one O(5), one O(7), two equivalent O(3), and two equivalent O(8) 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(1) and one O(2) atom. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(4) atom. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(6) atom. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(7) and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one C(2) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Ba(1), one Ba(2), and one C(2) atom. In the fifth 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 sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one C(3) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(4) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one C(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba(CO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.015
_cell_length_b   9.569
_cell_length_c   8.946
_cell_angle_alpha   88.063
_cell_angle_beta   85.441
_cell_angle_gamma   78.787
_symmetry_Int_Tables_number   1
_cell_volume   419.728
_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
  Ba  Ba0  1  0.980  0.736  0.421  1.0
  Ba  Ba1  1  0.020  0.264  0.579  1.0
  Ba  Ba2  1  0.040  0.255  0.073  1.0
  Ba  Ba3  1  0.960  0.745  0.927  1.0
  C  C4  1  0.481  0.558  0.681  1.0
  C  C5  1  0.519  0.442  0.319  1.0
  C  C6  1  0.434  0.441  0.804  1.0
  C  C7  1  0.566  0.559  0.196  1.0
  C  C8  1  0.599  0.006  0.684  1.0
  C  C9  1  0.401  0.994  0.316  1.0
  C  C10  1  0.371  0.989  0.810  1.0
  C  C11  1  0.629  0.011  0.190  1.0
  O  O12  1  0.284  0.662  0.668  1.0
  O  O13  1  0.716  0.338  0.332  1.0
  O  O14  1  0.709  0.540  0.605  1.0
  O  O15  1  0.291  0.460  0.395  1.0
  O  O16  1  0.187  0.449  0.857  1.0
  O  O17  1  0.813  0.551  0.143  1.0
  O  O18  1  0.636  0.350  0.841  1.0
  O  O19  1  0.364  0.650  0.159  1.0
  O  O20  1  0.801  0.903  0.670  1.0
  O  O21  1  0.199  0.097  0.330  1.0
  O  O22  1  0.569  0.121  0.607  1.0
  O  O23  1  0.431  0.879  0.393  1.0
  O  O24  1  0.159  0.087  0.820  1.0
  O  O25  1  0.841  0.913  0.180  1.0
  O  O26  1  0.412  0.879  0.894  1.0
  O  O27  1  0.588  0.121  0.106  1.0
[/CIF]
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The crystal structure described by BaC2O4 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(1), one O(3), one O(4), one O(5), one O(7), two equivalent O(2), and two equivalent O(6) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one O(1), one O(4), one O(5), one O(7), two equivalent O(3), and two equivalent O(8) 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(1) and one O(2) atom. In the second C site, C(2) is bonded in a distorted bent 120 degrees geometry to one O(3) and one O(4) atom. In the third C site, C(3) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(6) atom. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(7) and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one C(2) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Ba(1), one Ba(2), and one C(2) atom. In the fifth 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 sixth O site, O(6) is bonded in a distorted single-bond geometry to two equivalent Ba(1) and one C(3) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), and one C(4) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Ba(2) and one C(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba(CO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.015
_cell_length_b   9.569
_cell_length_c   8.946
_cell_angle_alpha   88.063
_cell_angle_beta   85.441
_cell_angle_gamma   78.787
_symmetry_Int_Tables_number   1
_cell_volume   419.728
_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
  Ba  Ba0  1  0.980  0.736  0.421  1.0
  Ba  Ba1  1  0.020  0.264  0.579  1.0
  Ba  Ba2  1  0.040  0.255  0.073  1.0
  Ba  Ba3  1  0.960  0.745  0.927  1.0
  C  C4  1  0.481  0.558  0.681  1.0
  C  C5  1  0.519  0.442  0.319  1.0
  C  C6  1  0.434  0.441  0.804  1.0
  C  C7  1  0.566  0.559  0.196  1.0
  C  C8  1  0.599  0.006  0.684  1.0
  C  C9  1  0.401  0.994  0.316  1.0
  C  C10  1  0.371  0.989  0.810  1.0
  C  C11  1  0.629  0.011  0.190  1.0
  O  O12  1  0.284  0.662  0.668  1.0
  O  O13  1  0.716  0.338  0.332  1.0
  O  O14  1  0.709  0.540  0.605  1.0
  O  O15  1  0.291  0.460  0.395  1.0
  O  O16  1  0.187  0.449  0.857  1.0
  O  O17  1  0.813  0.551  0.143  1.0
  O  O18  1  0.636  0.350  0.841  1.0
  O  O19  1  0.364  0.650  0.159  1.0
  O  O20  1  0.801  0.903  0.670  1.0
  O  O21  1  0.199  0.097  0.330  1.0
  O  O22  1  0.569  0.121  0.607  1.0
  O  O23  1  0.431  0.879  0.393  1.0
  O  O24  1  0.159  0.087  0.820  1.0
  O  O25  1  0.841  0.913  0.180  1.0
  O  O26  1  0.412  0.879  0.894  1.0
  O  O27  1  0.588  0.121  0.106  1.0
[/CIF]
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