The material structure described by Ba2Co2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(9), two equivalent O(5), and two equivalent O(7) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), two equivalent O(6), and two equivalent O(8) atoms. In the third Ba site, Ba(3) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), two equivalent O(5), and two equivalent O(7) atoms. In the fourth Ba site, Ba(4) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(9), two equivalent O(6), and two equivalent O(8) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), one O(3), one O(4), and one O(5) atom. In the second Co site, Co(2) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), one O(3), one O(4), and one O(8) atom. In the third Co site, Co(3) is bonded to one O(10), one O(5), one O(8), and one O(9) atom to form corner-sharing CoO4 tetrahedra. In the fourth Co site, Co(4) is bonded to one O(10), one O(6), one O(7), and one O(9) atom to form corner-sharing CoO4 tetrahedra. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Co(1), and one Co(2) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the second O site, O(2) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Co(1), and one Co(2) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the third O site, O(3) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Co(1), and one Co(2) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the fourth O site, O(4) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Co(1), and one Co(2) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), one Co(1), and one Co(3) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to two equivalent Ba(2), two equivalent Ba(4), and one Co(4) atom. In the seventh O site, O(7) is bonded in a 1-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), and one Co(4) atom. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Ba(4), one Co(2), and one Co(3) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(4), one Co(3), and one Co(4) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Ba(2), one Ba(3), one Co(3), and one Co(4) atom. is represented by the CIF card [CIF]
data_Ba2Co2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.613
_cell_length_b   5.677
_cell_length_c   9.669
_cell_angle_alpha   107.259
_cell_angle_beta   107.058
_cell_angle_gamma   89.391
_symmetry_Int_Tables_number   1
_cell_volume   280.316
_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  0.617  0.113  0.223  1.0
  Ba  Ba1  1  0.393  0.887  0.778  1.0
  Ba  Ba2  1  0.116  0.609  0.222  1.0
  Ba  Ba3  1  0.894  0.390  0.777  1.0
  Co  Co4  1  0.006  0.003  0.003  1.0
  Co  Co5  1  0.502  0.499  0.997  1.0
  Co  Co6  1  0.231  0.178  0.500  1.0
  Co  Co7  1  0.721  0.819  0.500  1.0
  O  O8  1  0.253  0.253  0.998  1.0
  O  O9  1  0.252  0.749  0.999  1.0
  O  O10  1  0.752  0.252  0.001  1.0
  O  O11  1  0.753  0.753  0.001  1.0
  O  O12  1  0.169  0.178  0.306  1.0
  O  O13  1  0.853  0.833  0.692  1.0
  O  O14  1  0.661  0.641  0.308  1.0
  O  O15  1  0.363  0.372  0.693  1.0
  O  O16  1  0.899  0.093  0.500  1.0
  O  O17  1  0.393  0.877  0.500  1.0
[/CIF]
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The material structure described by Ba2Co2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(9), two equivalent O(5), and two equivalent O(7) atoms. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), two equivalent O(6), and two equivalent O(8) atoms. In the third Ba site, Ba(3) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), two equivalent O(5), and two equivalent O(7) atoms. In the fourth Ba site, Ba(4) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(9), two equivalent O(6), and two equivalent O(8) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), one O(3), one O(4), and one O(5) atom. In the second Co site, Co(2) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), one O(3), one O(4), and one O(8) atom. In the third Co site, Co(3) is bonded to one O(10), one O(5), one O(8), and one O(9) atom to form corner-sharing CoO4 tetrahedra. In the fourth Co site, Co(4) is bonded to one O(10), one O(6), one O(7), and one O(9) atom to form corner-sharing CoO4 tetrahedra. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Co(1), and one Co(2) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the second O site, O(2) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Co(1), and one Co(2) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the third O site, O(3) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Co(1), and one Co(2) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the fourth O site, O(4) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Co(1), and one Co(2) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), one Co(1), and one Co(3) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to two equivalent Ba(2), two equivalent Ba(4), and one Co(4) atom. In the seventh O site, O(7) is bonded in a 1-coordinate geometry to two equivalent Ba(1), two equivalent Ba(3), and one Co(4) atom. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Ba(4), one Co(2), and one Co(3) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Ba(1), one Ba(4), one Co(3), and one Co(4) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Ba(2), one Ba(3), one Co(3), and one Co(4) atom. is represented by the CIF card [CIF]
data_Ba2Co2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.613
_cell_length_b   5.677
_cell_length_c   9.669
_cell_angle_alpha   107.259
_cell_angle_beta   107.058
_cell_angle_gamma   89.391
_symmetry_Int_Tables_number   1
_cell_volume   280.316
_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  0.617  0.113  0.223  1.0
  Ba  Ba1  1  0.393  0.887  0.778  1.0
  Ba  Ba2  1  0.116  0.609  0.222  1.0
  Ba  Ba3  1  0.894  0.390  0.777  1.0
  Co  Co4  1  0.006  0.003  0.003  1.0
  Co  Co5  1  0.502  0.499  0.997  1.0
  Co  Co6  1  0.231  0.178  0.500  1.0
  Co  Co7  1  0.721  0.819  0.500  1.0
  O  O8  1  0.253  0.253  0.998  1.0
  O  O9  1  0.252  0.749  0.999  1.0
  O  O10  1  0.752  0.252  0.001  1.0
  O  O11  1  0.753  0.753  0.001  1.0
  O  O12  1  0.169  0.178  0.306  1.0
  O  O13  1  0.853  0.833  0.692  1.0
  O  O14  1  0.661  0.641  0.308  1.0
  O  O15  1  0.363  0.372  0.693  1.0
  O  O16  1  0.899  0.093  0.500  1.0
  O  O17  1  0.393  0.877  0.500  1.0
[/CIF]
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