The material structure described by Ba3CoNb2O9 is (Cubic) Perovskite-derived structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(2), two equivalent O(4), four equivalent O(1), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ba(2)O12 cuboctahedra, faces with six equivalent Ba(2)O12 cuboctahedra, faces with two equivalent Co(1)O6 octahedra, and faces with six equivalent Nb(1)O6 octahedra. In the second Ba site, Ba(2) is bonded to one O(2), two equivalent O(1), three equivalent O(4), and six equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with nine equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Co(1)O6 octahedra, and faces with five equivalent Nb(1)O6 octahedra. Nb(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with three equivalent Nb(1)O6 octahedra, corners with three equivalent Co(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, and faces with five equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-3°. Co(1) is bonded to two equivalent O(4) and four equivalent O(3) atoms to form CoO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with six equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 3°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms to form distorted OBa4Nb2 octahedra that share corners with two equivalent O(2)Ba4Nb2 octahedra, corners with four equivalent O(1)Ba4Nb2 octahedra, corners with ten equivalent O(3)Ba4NbCo octahedra, edges with four equivalent O(3)Ba4NbCo octahedra, faces with two equivalent O(1)Ba4Nb2 octahedra, faces with two equivalent O(2)Ba4Nb2 octahedra, and faces with two equivalent O(3)Ba4NbCo octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms to form distorted OBa4Nb2 octahedra that share corners with two equivalent O(2)Ba4Nb2 octahedra, corners with four equivalent O(1)Ba4Nb2 octahedra, corners with twelve equivalent O(3)Ba4NbCo octahedra, faces with four equivalent O(1)Ba4Nb2 octahedra, and faces with four equivalent O(3)Ba4NbCo octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the third O site, O(3) is bonded to one Ba(1), three equivalent Ba(2), one Nb(1), and one Co(1) atom to form distorted OBa4NbCo octahedra that share corners with three equivalent O(2)Ba4Nb2 octahedra, corners with five equivalent O(1)Ba4Nb2 octahedra, corners with nine equivalent O(3)Ba4NbCo octahedra, edges with two equivalent O(1)Ba4Nb2 octahedra, edges with two equivalent O(3)Ba4NbCo octahedra,  a faceface with one O(1)Ba4Nb2 octahedra,  a faceface with one O(2)Ba4Nb2 octahedra, and faces with three equivalent O(3)Ba4NbCo octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), one Nb(1), and one Co(1) atom. is represented by the CIF file [CIF]
data_Ba3Nb2CoO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.870
_cell_length_b   5.854
_cell_length_c   7.191
_cell_angle_alpha   89.904
_cell_angle_beta   89.986
_cell_angle_gamma   119.999
_symmetry_Int_Tables_number   1
_cell_volume   213.998
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Ba  Ba1  1  0.332  0.666  0.665  1.0
  Ba  Ba2  1  0.668  0.334  0.335  1.0
  Nb  Nb3  1  0.333  0.667  0.178  1.0
  Nb  Nb4  1  0.667  0.333  0.822  1.0
  Co  Co5  1  0.000  0.000  0.500  1.0
  O  O6  1  0.500  0.500  0.000  1.0
  O  O7  1  0.500  0.000  0.000  1.0
  O  O8  1  0.000  0.500  0.000  1.0
  O  O9  1  0.171  0.828  0.325  1.0
  O  O10  1  0.171  0.342  0.326  1.0
  O  O11  1  0.657  0.828  0.325  1.0
  O  O12  1  0.829  0.172  0.675  1.0
  O  O13  1  0.829  0.658  0.674  1.0
  O  O14  1  0.343  0.172  0.675  1.0
[/CIF]
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The material structure described by Ba3CoNb2O9 is (Cubic) Perovskite-derived structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(2), two equivalent O(4), four equivalent O(1), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ba(2)O12 cuboctahedra, faces with six equivalent Ba(2)O12 cuboctahedra, faces with two equivalent Co(1)O6 octahedra, and faces with six equivalent Nb(1)O6 octahedra. In the second Ba site, Ba(2) is bonded to one O(2), two equivalent O(1), three equivalent O(4), and six equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with nine equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Co(1)O6 octahedra, and faces with five equivalent Nb(1)O6 octahedra. Nb(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with three equivalent Nb(1)O6 octahedra, corners with three equivalent Co(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, and faces with five equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-3°. Co(1) is bonded to two equivalent O(4) and four equivalent O(3) atoms to form CoO6 octahedra that share corners with six equivalent Nb(1)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with six equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 3°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms to form distorted OBa4Nb2 octahedra that share corners with two equivalent O(2)Ba4Nb2 octahedra, corners with four equivalent O(1)Ba4Nb2 octahedra, corners with ten equivalent O(3)Ba4NbCo octahedra, edges with four equivalent O(3)Ba4NbCo octahedra, faces with two equivalent O(1)Ba4Nb2 octahedra, faces with two equivalent O(2)Ba4Nb2 octahedra, and faces with two equivalent O(3)Ba4NbCo octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Nb(1) atoms to form distorted OBa4Nb2 octahedra that share corners with two equivalent O(2)Ba4Nb2 octahedra, corners with four equivalent O(1)Ba4Nb2 octahedra, corners with twelve equivalent O(3)Ba4NbCo octahedra, faces with four equivalent O(1)Ba4Nb2 octahedra, and faces with four equivalent O(3)Ba4NbCo octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the third O site, O(3) is bonded to one Ba(1), three equivalent Ba(2), one Nb(1), and one Co(1) atom to form distorted OBa4NbCo octahedra that share corners with three equivalent O(2)Ba4Nb2 octahedra, corners with five equivalent O(1)Ba4Nb2 octahedra, corners with nine equivalent O(3)Ba4NbCo octahedra, edges with two equivalent O(1)Ba4Nb2 octahedra, edges with two equivalent O(3)Ba4NbCo octahedra,  a faceface with one O(1)Ba4Nb2 octahedra,  a faceface with one O(2)Ba4Nb2 octahedra, and faces with three equivalent O(3)Ba4NbCo octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), one Nb(1), and one Co(1) atom. is represented by the CIF file [CIF]
data_Ba3Nb2CoO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.870
_cell_length_b   5.854
_cell_length_c   7.191
_cell_angle_alpha   89.904
_cell_angle_beta   89.986
_cell_angle_gamma   119.999
_symmetry_Int_Tables_number   1
_cell_volume   213.998
_cell_formula_units_Z   1
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  0.000  0.000  0.000  1.0
  Ba  Ba1  1  0.332  0.666  0.665  1.0
  Ba  Ba2  1  0.668  0.334  0.335  1.0
  Nb  Nb3  1  0.333  0.667  0.178  1.0
  Nb  Nb4  1  0.667  0.333  0.822  1.0
  Co  Co5  1  0.000  0.000  0.500  1.0
  O  O6  1  0.500  0.500  0.000  1.0
  O  O7  1  0.500  0.000  0.000  1.0
  O  O8  1  0.000  0.500  0.000  1.0
  O  O9  1  0.171  0.828  0.325  1.0
  O  O10  1  0.171  0.342  0.326  1.0
  O  O11  1  0.657  0.828  0.325  1.0
  O  O12  1  0.829  0.172  0.675  1.0
  O  O13  1  0.829  0.658  0.674  1.0
  O  O14  1  0.343  0.172  0.675  1.0
[/CIF]
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