The material structure described by BaNb5O8 crystallizes in the tetragonal P4/m space group. Ba(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with eight equivalent Nb(1)O5 square pyramids, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with eight equivalent Nb(1)O5 square pyramids. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2) and three equivalent O(1) atoms to form NbO5 square pyramids that share corners with two equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Nb(1)O5 square pyramids,  an edgeedge with one Nb(1)O5 square pyramid, and faces with two equivalent Ba(1)O12 cuboctahedra. In the second Nb site, Nb(2) is bonded in a square co-planar geometry to four equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to two equivalent Ba(1) and three equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Ba(1), one Nb(2), and two equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_BaNb5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.671
_cell_length_b   7.860
_cell_length_c   4.151
_cell_angle_alpha   58.135
_cell_angle_beta   89.999
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   184.870
_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  0.994  1.0
  Nb  Nb1  1  0.212  0.402  0.092  1.0
  Nb  Nb2  1  0.402  0.788  0.706  1.0
  Nb  Nb3  1  0.500  0.500  0.494  1.0
  Nb  Nb4  1  0.598  0.212  0.282  1.0
  Nb  Nb5  1  0.788  0.598  0.896  1.0
  O  O6  1  0.099  0.699  0.795  1.0
  O  O7  1  0.204  0.387  0.607  1.0
  O  O8  1  0.301  0.099  0.395  1.0
  O  O9  1  0.387  0.796  0.198  1.0
  O  O10  1  0.613  0.204  0.790  1.0
  O  O11  1  0.699  0.901  0.593  1.0
  O  O12  1  0.796  0.613  0.381  1.0
  O  O13  1  0.901  0.301  0.193  1.0
[/CIF]
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The material structure described by BaNb5O8 crystallizes in the tetragonal P4/m space group. Ba(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with eight equivalent Nb(1)O5 square pyramids, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with eight equivalent Nb(1)O5 square pyramids. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2) and three equivalent O(1) atoms to form NbO5 square pyramids that share corners with two equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Nb(1)O5 square pyramids,  an edgeedge with one Nb(1)O5 square pyramid, and faces with two equivalent Ba(1)O12 cuboctahedra. In the second Nb site, Nb(2) is bonded in a square co-planar geometry to four equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to two equivalent Ba(1) and three equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Ba(1), one Nb(2), and two equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_BaNb5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.671
_cell_length_b   7.860
_cell_length_c   4.151
_cell_angle_alpha   58.135
_cell_angle_beta   89.999
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   184.870
_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  0.994  1.0
  Nb  Nb1  1  0.212  0.402  0.092  1.0
  Nb  Nb2  1  0.402  0.788  0.706  1.0
  Nb  Nb3  1  0.500  0.500  0.494  1.0
  Nb  Nb4  1  0.598  0.212  0.282  1.0
  Nb  Nb5  1  0.788  0.598  0.896  1.0
  O  O6  1  0.099  0.699  0.795  1.0
  O  O7  1  0.204  0.387  0.607  1.0
  O  O8  1  0.301  0.099  0.395  1.0
  O  O9  1  0.387  0.796  0.198  1.0
  O  O10  1  0.613  0.204  0.790  1.0
  O  O11  1  0.699  0.901  0.593  1.0
  O  O12  1  0.796  0.613  0.381  1.0
  O  O13  1  0.901  0.301  0.193  1.0
[/CIF]
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