The material structure described by BaNb2Fe2O9 crystallizes in the orthorhombic Cmc2_1 space group. Ba(1) is bonded to four equivalent O(1), four equivalent O(4), and four equivalent O(5) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with eight equivalent Nb(1)O6 octahedra. Nb(1) is bonded to one O(1), one O(2), two equivalent O(4), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with five equivalent Nb(1)O6 octahedra and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 4-14°. Fe(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Ba(1) and two equivalent Nb(1) atoms. In the second O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Nb(1) atoms to form a mixture of edge and corner-sharing OBa4Nb2 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. In the third O site, O(2) is bonded in a linear geometry to one Nb(1) and one Fe(1) atom. In the fourth O site, O(3) is bonded to four equivalent Fe(1) atoms to form a mixture of distorted edge and corner-sharing OFe4 trigonal pyramids. In the fifth O site, O(4) is bonded in a distorted linear geometry to two equivalent Ba(1) and two equivalent Nb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaNb2Fe2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.492
_cell_length_b   13.492
_cell_length_c   5.625
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   155.945
_symmetry_Int_Tables_number   1
_cell_volume   417.371
_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  0.751  0.536  1.0
  Ba  Ba1  1  0.249  0.249  0.036  1.0
  Nb  Nb2  1  0.666  0.833  0.042  1.0
  Nb  Nb3  1  0.833  0.666  0.042  1.0
  Nb  Nb4  1  0.334  0.167  0.542  1.0
  Nb  Nb5  1  0.167  0.334  0.542  1.0
  Fe  Fe6  1  0.524  0.973  0.002  1.0
  Fe  Fe7  1  0.973  0.524  0.002  1.0
  Fe  Fe8  1  0.476  0.027  0.502  1.0
  Fe  Fe9  1  0.027  0.476  0.502  1.0
  O  O10  1  0.756  0.756  0.029  1.0
  O  O11  1  0.244  0.244  0.529  1.0
  O  O12  1  0.582  0.894  0.014  1.0
  O  O13  1  0.894  0.582  0.014  1.0
  O  O14  1  0.418  0.106  0.514  1.0
  O  O15  1  0.106  0.418  0.514  1.0
  O  O16  1  0.250  0.752  0.753  1.0
  O  O17  1  0.752  0.250  0.753  1.0
  O  O18  1  0.750  0.248  0.253  1.0
  O  O19  1  0.248  0.750  0.253  1.0
  O  O20  1  0.077  0.922  0.775  1.0
  O  O21  1  0.922  0.077  0.775  1.0
  O  O22  1  0.923  0.078  0.275  1.0
  O  O23  1  0.078  0.923  0.275  1.0
  O  O24  1  0.576  0.426  0.775  1.0
  O  O25  1  0.426  0.576  0.775  1.0
  O  O26  1  0.424  0.574  0.275  1.0
  O  O27  1  0.574  0.424  0.275  1.0
[/CIF]
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The material structure described by BaNb2Fe2O9 crystallizes in the orthorhombic Cmc2_1 space group. Ba(1) is bonded to four equivalent O(1), four equivalent O(4), and four equivalent O(5) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with eight equivalent Nb(1)O6 octahedra. Nb(1) is bonded to one O(1), one O(2), two equivalent O(4), and two equivalent O(5) atoms to form NbO6 octahedra that share corners with five equivalent Nb(1)O6 octahedra and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 4-14°. Fe(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Ba(1) and two equivalent Nb(1) atoms. In the second O site, O(1) is bonded to four equivalent Ba(1) and two equivalent Nb(1) atoms to form a mixture of edge and corner-sharing OBa4Nb2 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. In the third O site, O(2) is bonded in a linear geometry to one Nb(1) and one Fe(1) atom. In the fourth O site, O(3) is bonded to four equivalent Fe(1) atoms to form a mixture of distorted edge and corner-sharing OFe4 trigonal pyramids. In the fifth O site, O(4) is bonded in a distorted linear geometry to two equivalent Ba(1) and two equivalent Nb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaNb2Fe2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.492
_cell_length_b   13.492
_cell_length_c   5.625
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   155.945
_symmetry_Int_Tables_number   1
_cell_volume   417.371
_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  0.751  0.536  1.0
  Ba  Ba1  1  0.249  0.249  0.036  1.0
  Nb  Nb2  1  0.666  0.833  0.042  1.0
  Nb  Nb3  1  0.833  0.666  0.042  1.0
  Nb  Nb4  1  0.334  0.167  0.542  1.0
  Nb  Nb5  1  0.167  0.334  0.542  1.0
  Fe  Fe6  1  0.524  0.973  0.002  1.0
  Fe  Fe7  1  0.973  0.524  0.002  1.0
  Fe  Fe8  1  0.476  0.027  0.502  1.0
  Fe  Fe9  1  0.027  0.476  0.502  1.0
  O  O10  1  0.756  0.756  0.029  1.0
  O  O11  1  0.244  0.244  0.529  1.0
  O  O12  1  0.582  0.894  0.014  1.0
  O  O13  1  0.894  0.582  0.014  1.0
  O  O14  1  0.418  0.106  0.514  1.0
  O  O15  1  0.106  0.418  0.514  1.0
  O  O16  1  0.250  0.752  0.753  1.0
  O  O17  1  0.752  0.250  0.753  1.0
  O  O18  1  0.750  0.248  0.253  1.0
  O  O19  1  0.248  0.750  0.253  1.0
  O  O20  1  0.077  0.922  0.775  1.0
  O  O21  1  0.922  0.077  0.775  1.0
  O  O22  1  0.923  0.078  0.275  1.0
  O  O23  1  0.078  0.923  0.275  1.0
  O  O24  1  0.576  0.426  0.775  1.0
  O  O25  1  0.426  0.576  0.775  1.0
  O  O26  1  0.424  0.574  0.275  1.0
  O  O27  1  0.574  0.424  0.275  1.0
[/CIF]
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