The material described by BaF2 crystallizes in the hexagonal P6_3/mmc space group. Ba(1) is bonded in a 11-coordinate geometry to five equivalent F(2) and six equivalent F(1) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded to six equivalent Ba(1) atoms to form FBa6 octahedra that share corners with twelve equivalent F(1)Ba6 octahedra, corners with twelve equivalent F(2)Ba5 trigonal bipyramids, edges with six equivalent F(1)Ba6 octahedra, faces with two equivalent F(1)Ba6 octahedra, and faces with six equivalent F(2)Ba5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 51°. In the second F site, F(2) is bonded to five equivalent Ba(1) atoms to form FBa5 trigonal bipyramids that share corners with twelve equivalent F(1)Ba6 octahedra, corners with eight equivalent F(2)Ba5 trigonal bipyramids, edges with six equivalent F(2)Ba5 trigonal bipyramids, and faces with six equivalent F(1)Ba6 octahedra. The corner-sharing octahedral tilt angles range from 31-59°. is represented by the CIF file [CIF]
data_BaF2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.455
_cell_length_b   4.455
_cell_length_c   6.217
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   106.871
_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  0.667  0.333  0.750  1.0
  Ba  Ba1  1  0.333  0.667  0.250  1.0
  F  F2  1  0.000  0.000  0.500  1.0
  F  F3  1  0.000  0.000  0.000  1.0
  F  F4  1  0.333  0.667  0.750  1.0
  F  F5  1  0.667  0.333  0.250  1.0
[/CIF]
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The material described by BaF2 crystallizes in the hexagonal P6_3/mmc space group. Ba(1) is bonded in a 11-coordinate geometry to five equivalent F(2) and six equivalent F(1) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded to six equivalent Ba(1) atoms to form FBa6 octahedra that share corners with twelve equivalent F(1)Ba6 octahedra, corners with twelve equivalent F(2)Ba5 trigonal bipyramids, edges with six equivalent F(1)Ba6 octahedra, faces with two equivalent F(1)Ba6 octahedra, and faces with six equivalent F(2)Ba5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 51°. In the second F site, F(2) is bonded to five equivalent Ba(1) atoms to form FBa5 trigonal bipyramids that share corners with twelve equivalent F(1)Ba6 octahedra, corners with eight equivalent F(2)Ba5 trigonal bipyramids, edges with six equivalent F(2)Ba5 trigonal bipyramids, and faces with six equivalent F(1)Ba6 octahedra. The corner-sharing octahedral tilt angles range from 31-59°. is represented by the CIF file [CIF]
data_BaF2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.455
_cell_length_b   4.455
_cell_length_c   6.217
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   106.871
_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  0.667  0.333  0.750  1.0
  Ba  Ba1  1  0.333  0.667  0.250  1.0
  F  F2  1  0.000  0.000  0.500  1.0
  F  F3  1  0.000  0.000  0.000  1.0
  F  F4  1  0.333  0.667  0.750  1.0
  F  F5  1  0.667  0.333  0.250  1.0
[/CIF]
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