The structure described by Sr3Ta4(O6F)2 crystallizes in the trigonal R-3m space group. Sr(1) is bonded to two equivalent O(2), four equivalent O(1), and two equivalent F(1) atoms to form distorted SrO6F2 hexagonal bipyramids that share edges with four equivalent Sr(1)O6F2 hexagonal bipyramids, edges with two equivalent Ta(2)O6 octahedra, and edges with four equivalent Ta(1)O6 octahedra. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with four equivalent Ta(1)O6 octahedra, and edges with four equivalent Sr(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 37-42°. In the second Ta site, Ta(2) is bonded to six equivalent O(1) atoms to form TaO6 octahedra that share corners with six equivalent Ta(1)O6 octahedra and edges with six equivalent Sr(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 42°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Ta(1), and one Ta(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1) and two equivalent Ta(1) atoms. F(1) is bonded in a trigonal non-coplanar geometry to three equivalent Sr(1) atoms. is represented by the CIF card [CIF]
data_Sr3Ta4(O6F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.488
_cell_length_b   7.488
_cell_length_c   7.488
_cell_angle_alpha   61.164
_cell_angle_beta   61.164
_cell_angle_gamma   61.164
_symmetry_Int_Tables_number   1
_cell_volume   304.709
_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
  Sr  Sr0  1  0.500  0.500  0.000  1.0
  Sr  Sr1  1  0.000  0.500  0.500  1.0
  Sr  Sr2  1  0.500  0.000  0.500  1.0
  Ta  Ta3  1  0.000  0.500  0.000  1.0
  Ta  Ta4  1  0.000  0.000  0.000  1.0
  Ta  Ta5  1  0.500  0.000  0.000  1.0
  Ta  Ta6  1  0.000  0.000  0.500  1.0
  O  O7  1  0.067  0.686  0.067  1.0
  O  O8  1  0.933  0.314  0.933  1.0
  O  O9  1  0.691  0.691  0.052  1.0
  O  O10  1  0.052  0.691  0.691  1.0
  O  O11  1  0.686  0.067  0.067  1.0
  O  O12  1  0.067  0.067  0.686  1.0
  O  O13  1  0.691  0.052  0.691  1.0
  O  O14  1  0.948  0.309  0.309  1.0
  O  O15  1  0.933  0.933  0.314  1.0
  O  O16  1  0.309  0.309  0.948  1.0
  O  O17  1  0.314  0.933  0.933  1.0
  O  O18  1  0.309  0.948  0.309  1.0
  F  F19  1  0.625  0.625  0.625  1.0
  F  F20  1  0.375  0.375  0.375  1.0
[/CIF]
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The structure described by Sr3Ta4(O6F)2 crystallizes in the trigonal R-3m space group. Sr(1) is bonded to two equivalent O(2), four equivalent O(1), and two equivalent F(1) atoms to form distorted SrO6F2 hexagonal bipyramids that share edges with four equivalent Sr(1)O6F2 hexagonal bipyramids, edges with two equivalent Ta(2)O6 octahedra, and edges with four equivalent Ta(1)O6 octahedra. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with four equivalent Ta(1)O6 octahedra, and edges with four equivalent Sr(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 37-42°. In the second Ta site, Ta(2) is bonded to six equivalent O(1) atoms to form TaO6 octahedra that share corners with six equivalent Ta(1)O6 octahedra and edges with six equivalent Sr(1)O6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 42°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Ta(1), and one Ta(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1) and two equivalent Ta(1) atoms. F(1) is bonded in a trigonal non-coplanar geometry to three equivalent Sr(1) atoms. is represented by the CIF card [CIF]
data_Sr3Ta4(O6F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.488
_cell_length_b   7.488
_cell_length_c   7.488
_cell_angle_alpha   61.164
_cell_angle_beta   61.164
_cell_angle_gamma   61.164
_symmetry_Int_Tables_number   1
_cell_volume   304.709
_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
  Sr  Sr0  1  0.500  0.500  0.000  1.0
  Sr  Sr1  1  0.000  0.500  0.500  1.0
  Sr  Sr2  1  0.500  0.000  0.500  1.0
  Ta  Ta3  1  0.000  0.500  0.000  1.0
  Ta  Ta4  1  0.000  0.000  0.000  1.0
  Ta  Ta5  1  0.500  0.000  0.000  1.0
  Ta  Ta6  1  0.000  0.000  0.500  1.0
  O  O7  1  0.067  0.686  0.067  1.0
  O  O8  1  0.933  0.314  0.933  1.0
  O  O9  1  0.691  0.691  0.052  1.0
  O  O10  1  0.052  0.691  0.691  1.0
  O  O11  1  0.686  0.067  0.067  1.0
  O  O12  1  0.067  0.067  0.686  1.0
  O  O13  1  0.691  0.052  0.691  1.0
  O  O14  1  0.948  0.309  0.309  1.0
  O  O15  1  0.933  0.933  0.314  1.0
  O  O16  1  0.309  0.309  0.948  1.0
  O  O17  1  0.314  0.933  0.933  1.0
  O  O18  1  0.309  0.948  0.309  1.0
  F  F19  1  0.625  0.625  0.625  1.0
  F  F20  1  0.375  0.375  0.375  1.0
[/CIF]
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