The structure described by KCaNb2O6F crystallizes in the orthorhombic Imma space group. K(1) is bonded to two equivalent O(2), four equivalent O(1), and two equivalent F(1) atoms to form distorted KO6F2 hexagonal bipyramids that share edges with two equivalent K(1)O6F2 hexagonal bipyramids, edges with four equivalent Ca(1)O6F2 hexagonal bipyramids, edges with two equivalent Nb(2)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. Ca(1) is bonded to two equivalent O(3), four equivalent O(1), and two equivalent F(1) atoms to form distorted CaO6F2 hexagonal bipyramids that share edges with two equivalent Ca(1)O6F2 hexagonal bipyramids, edges with four equivalent K(1)O6F2 hexagonal bipyramids, edges with two equivalent Nb(1)O6 octahedra, and edges with four equivalent Nb(2)O6 octahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, edges with two equivalent Ca(1)O6F2 hexagonal bipyramids, and edges with four equivalent K(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 37-40°. In the second Nb site, Nb(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, edges with two equivalent K(1)O6F2 hexagonal bipyramids, and edges with four equivalent Ca(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 40-43°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one K(1), one Ca(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent K(1) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1) and two equivalent Nb(2) atoms. F(1) is bonded to two equivalent K(1) and two equivalent Ca(1) atoms to form corner-sharing FK2Ca2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_KCaNb2O6F
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.592
_cell_length_b   7.592
_cell_length_c   7.592
_cell_angle_alpha   120.910
_cell_angle_beta   119.494
_cell_angle_gamma   89.654
_symmetry_Int_Tables_number   1
_cell_volume   308.461
_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
  K  K0  1  0.000  0.500  0.000  1.0
  K  K1  1  0.000  0.000  0.500  1.0
  Ca  Ca2  1  0.000  0.500  0.500  1.0
  Ca  Ca3  1  0.500  0.500  0.000  1.0
  Nb  Nb4  1  0.500  0.000  0.500  1.0
  Nb  Nb5  1  0.500  0.500  0.500  1.0
  Nb  Nb6  1  0.000  0.000  0.000  1.0
  Nb  Nb7  1  0.500  0.000  0.000  1.0
  O  O8  1  0.187  0.928  0.870  1.0
  O  O9  1  0.191  0.941  0.250  1.0
  O  O10  1  0.187  0.317  0.259  1.0
  O  O11  1  0.558  0.928  0.241  1.0
  O  O12  1  0.442  0.683  0.370  1.0
  O  O13  1  0.431  0.681  0.750  1.0
  O  O14  1  0.569  0.319  0.250  1.0
  O  O15  1  0.558  0.317  0.630  1.0
  O  O16  1  0.442  0.072  0.759  1.0
  O  O17  1  0.813  0.683  0.741  1.0
  O  O18  1  0.809  0.059  0.750  1.0
  O  O19  1  0.813  0.072  0.130  1.0
  F  F20  1  0.847  0.597  0.250  1.0
  F  F21  1  0.153  0.403  0.750  1.0
[/CIF]
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The structure described by KCaNb2O6F crystallizes in the orthorhombic Imma space group. K(1) is bonded to two equivalent O(2), four equivalent O(1), and two equivalent F(1) atoms to form distorted KO6F2 hexagonal bipyramids that share edges with two equivalent K(1)O6F2 hexagonal bipyramids, edges with four equivalent Ca(1)O6F2 hexagonal bipyramids, edges with two equivalent Nb(2)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. Ca(1) is bonded to two equivalent O(3), four equivalent O(1), and two equivalent F(1) atoms to form distorted CaO6F2 hexagonal bipyramids that share edges with two equivalent Ca(1)O6F2 hexagonal bipyramids, edges with four equivalent K(1)O6F2 hexagonal bipyramids, edges with two equivalent Nb(1)O6 octahedra, and edges with four equivalent Nb(2)O6 octahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, edges with two equivalent Ca(1)O6F2 hexagonal bipyramids, and edges with four equivalent K(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 37-40°. In the second Nb site, Nb(2) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with four equivalent Nb(1)O6 octahedra, edges with two equivalent K(1)O6F2 hexagonal bipyramids, and edges with four equivalent Ca(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 40-43°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one K(1), one Ca(1), one Nb(1), and one Nb(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent K(1) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ca(1) and two equivalent Nb(2) atoms. F(1) is bonded to two equivalent K(1) and two equivalent Ca(1) atoms to form corner-sharing FK2Ca2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_KCaNb2O6F
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.592
_cell_length_b   7.592
_cell_length_c   7.592
_cell_angle_alpha   120.910
_cell_angle_beta   119.494
_cell_angle_gamma   89.654
_symmetry_Int_Tables_number   1
_cell_volume   308.461
_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
  K  K0  1  0.000  0.500  0.000  1.0
  K  K1  1  0.000  0.000  0.500  1.0
  Ca  Ca2  1  0.000  0.500  0.500  1.0
  Ca  Ca3  1  0.500  0.500  0.000  1.0
  Nb  Nb4  1  0.500  0.000  0.500  1.0
  Nb  Nb5  1  0.500  0.500  0.500  1.0
  Nb  Nb6  1  0.000  0.000  0.000  1.0
  Nb  Nb7  1  0.500  0.000  0.000  1.0
  O  O8  1  0.187  0.928  0.870  1.0
  O  O9  1  0.191  0.941  0.250  1.0
  O  O10  1  0.187  0.317  0.259  1.0
  O  O11  1  0.558  0.928  0.241  1.0
  O  O12  1  0.442  0.683  0.370  1.0
  O  O13  1  0.431  0.681  0.750  1.0
  O  O14  1  0.569  0.319  0.250  1.0
  O  O15  1  0.558  0.317  0.630  1.0
  O  O16  1  0.442  0.072  0.759  1.0
  O  O17  1  0.813  0.683  0.741  1.0
  O  O18  1  0.809  0.059  0.750  1.0
  O  O19  1  0.813  0.072  0.130  1.0
  F  F20  1  0.847  0.597  0.250  1.0
  F  F21  1  0.153  0.403  0.750  1.0
[/CIF]
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