The material described by KBa2Nb3O9 is (Cubic) Perovskite-derived structured and crystallizes in the trigonal P-3m1 space group. K(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form KO12 cuboctahedra that share corners with six equivalent K(1)O12 cuboctahedra, corners with six equivalent Ba(1)O12 cuboctahedra, faces with six equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Nb(1)O6 octahedra, and faces with six equivalent Nb(2)O6 octahedra. Ba(1) is bonded to three equivalent O(2) and nine equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with three equivalent K(1)O12 cuboctahedra, corners with nine equivalent Ba(1)O12 cuboctahedra, faces with three equivalent K(1)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Nb(1)O6 octahedra, and faces with five equivalent Nb(2)O6 octahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to six equivalent O(1) atoms to form NbO6 octahedra that share corners with six equivalent Nb(2)O6 octahedra, faces with two equivalent K(1)O12 cuboctahedra, and faces with six equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 2°. In the second Nb site, Nb(2) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NbO6 octahedra that share corners with three equivalent Nb(1)O6 octahedra, corners with three equivalent Nb(2)O6 octahedra, faces with three equivalent K(1)O12 cuboctahedra, and faces with five equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one K(1), three equivalent Ba(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent K(1), two equivalent Ba(1), and two equivalent Nb(2) atoms. is represented by the CIF file [CIF]
data_KBa2Nb3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.835
_cell_length_b   5.835
_cell_length_c   7.139
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   210.473
_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
  K  K0  1  0.000  0.000  0.000  1.0
  Ba  Ba1  1  0.667  0.333  0.330  1.0
  Ba  Ba2  1  0.333  0.667  0.670  1.0
  Nb  Nb3  1  0.000  0.000  0.500  1.0
  Nb  Nb4  1  0.667  0.333  0.837  1.0
  Nb  Nb5  1  0.333  0.667  0.163  1.0
  O  O6  1  0.664  0.832  0.336  1.0
  O  O7  1  0.336  0.168  0.664  1.0
  O  O8  1  0.000  0.500  0.000  1.0
  O  O9  1  0.832  0.664  0.664  1.0
  O  O10  1  0.500  0.000  0.000  1.0
  O  O11  1  0.168  0.336  0.336  1.0
  O  O12  1  0.832  0.168  0.664  1.0
  O  O13  1  0.500  0.500  0.000  1.0
  O  O14  1  0.168  0.832  0.336  1.0
[/CIF]
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The material described by KBa2Nb3O9 is (Cubic) Perovskite-derived structured and crystallizes in the trigonal P-3m1 space group. K(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form KO12 cuboctahedra that share corners with six equivalent K(1)O12 cuboctahedra, corners with six equivalent Ba(1)O12 cuboctahedra, faces with six equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Nb(1)O6 octahedra, and faces with six equivalent Nb(2)O6 octahedra. Ba(1) is bonded to three equivalent O(2) and nine equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with three equivalent K(1)O12 cuboctahedra, corners with nine equivalent Ba(1)O12 cuboctahedra, faces with three equivalent K(1)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Nb(1)O6 octahedra, and faces with five equivalent Nb(2)O6 octahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to six equivalent O(1) atoms to form NbO6 octahedra that share corners with six equivalent Nb(2)O6 octahedra, faces with two equivalent K(1)O12 cuboctahedra, and faces with six equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 2°. In the second Nb site, Nb(2) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NbO6 octahedra that share corners with three equivalent Nb(1)O6 octahedra, corners with three equivalent Nb(2)O6 octahedra, faces with three equivalent K(1)O12 cuboctahedra, and faces with five equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one K(1), three equivalent Ba(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent K(1), two equivalent Ba(1), and two equivalent Nb(2) atoms. is represented by the CIF file [CIF]
data_KBa2Nb3O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.835
_cell_length_b   5.835
_cell_length_c   7.139
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   210.473
_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
  K  K0  1  0.000  0.000  0.000  1.0
  Ba  Ba1  1  0.667  0.333  0.330  1.0
  Ba  Ba2  1  0.333  0.667  0.670  1.0
  Nb  Nb3  1  0.000  0.000  0.500  1.0
  Nb  Nb4  1  0.667  0.333  0.837  1.0
  Nb  Nb5  1  0.333  0.667  0.163  1.0
  O  O6  1  0.664  0.832  0.336  1.0
  O  O7  1  0.336  0.168  0.664  1.0
  O  O8  1  0.000  0.500  0.000  1.0
  O  O9  1  0.832  0.664  0.664  1.0
  O  O10  1  0.500  0.000  0.000  1.0
  O  O11  1  0.168  0.336  0.336  1.0
  O  O12  1  0.832  0.168  0.664  1.0
  O  O13  1  0.500  0.500  0.000  1.0
  O  O14  1  0.168  0.832  0.336  1.0
[/CIF]
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