The structure described by RbBa2Fe2F9 crystallizes in the trigonal R3m space group. Rb(1) is bonded to three equivalent F(1), three equivalent F(3), and six equivalent F(2) atoms to form distorted RbF12 cuboctahedra that share corners with six equivalent Rb(1)F12 cuboctahedra, corners with three equivalent Fe(1)F6 octahedra, faces with four equivalent Ba(1)F12 cuboctahedra,  a faceface with one Fe(1)F6 octahedra, and faces with three equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles are 25°. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to three equivalent F(1), three equivalent F(2), and six equivalent F(3) atoms to form BaF12 cuboctahedra that share corners with six equivalent Ba(1)F12 cuboctahedra, faces with four equivalent Rb(1)F12 cuboctahedra, faces with three equivalent Fe(1)F6 octahedra, and faces with three equivalent Fe(2)F6 octahedra. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to three equivalent F(2), three equivalent F(3), and six equivalent F(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent F(1) and three equivalent F(3) atoms to form FeF6 octahedra that share corners with three equivalent Rb(1)F12 cuboctahedra, corners with three equivalent Fe(2)F6 octahedra,  a faceface with one Rb(1)F12 cuboctahedra, and faces with three equivalent Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. In the second Fe site, Fe(2) is bonded to three equivalent F(2) and three equivalent F(3) atoms to form FeF6 octahedra that share corners with three equivalent Fe(1)F6 octahedra, faces with three equivalent Rb(1)F12 cuboctahedra, and faces with three equivalent Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. There are three inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to one Rb(1), one Ba(1), two equivalent Ba(2), and one Fe(1) atom. In the second F site, F(2) is bonded in a 5-coordinate geometry to two equivalent Rb(1), one Ba(1), one Ba(2), and one Fe(2) atom. In the third F site, F(3) is bonded in a distorted linear geometry to one Rb(1), one Ba(2), two equivalent Ba(1), one Fe(1), and one Fe(2) atom. is represented by the CIF card [CIF]
data_RbBa2Fe2F9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.857
_cell_length_b   7.857
_cell_length_c   7.857
_cell_angle_alpha   44.833
_cell_angle_beta   44.833
_cell_angle_gamma   44.833
_symmetry_Int_Tables_number   1
_cell_volume   219.357
_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
  Rb  Rb0  1  0.213  0.213  0.213  1.0
  Ba  Ba1  1  0.999  0.999  0.999  1.0
  Ba  Ba2  1  0.793  0.793  0.793  1.0
  Fe  Fe3  1  0.392  0.392  0.392  1.0
  Fe  Fe4  1  0.604  0.604  0.604  1.0
  F  F5  1  0.266  0.782  0.266  1.0
  F  F6  1  0.782  0.266  0.266  1.0
  F  F7  1  0.266  0.266  0.782  1.0
  F  F8  1  0.735  0.210  0.735  1.0
  F  F9  1  0.210  0.735  0.735  1.0
  F  F10  1  0.735  0.735  0.210  1.0
  F  F11  1  0.993  0.506  0.506  1.0
  F  F12  1  0.506  0.506  0.993  1.0
  F  F13  1  0.506  0.993  0.506  1.0
[/CIF]
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The structure described by RbBa2Fe2F9 crystallizes in the trigonal R3m space group. Rb(1) is bonded to three equivalent F(1), three equivalent F(3), and six equivalent F(2) atoms to form distorted RbF12 cuboctahedra that share corners with six equivalent Rb(1)F12 cuboctahedra, corners with three equivalent Fe(1)F6 octahedra, faces with four equivalent Ba(1)F12 cuboctahedra,  a faceface with one Fe(1)F6 octahedra, and faces with three equivalent Fe(2)F6 octahedra. The corner-sharing octahedral tilt angles are 25°. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to three equivalent F(1), three equivalent F(2), and six equivalent F(3) atoms to form BaF12 cuboctahedra that share corners with six equivalent Ba(1)F12 cuboctahedra, faces with four equivalent Rb(1)F12 cuboctahedra, faces with three equivalent Fe(1)F6 octahedra, and faces with three equivalent Fe(2)F6 octahedra. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to three equivalent F(2), three equivalent F(3), and six equivalent F(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent F(1) and three equivalent F(3) atoms to form FeF6 octahedra that share corners with three equivalent Rb(1)F12 cuboctahedra, corners with three equivalent Fe(2)F6 octahedra,  a faceface with one Rb(1)F12 cuboctahedra, and faces with three equivalent Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. In the second Fe site, Fe(2) is bonded to three equivalent F(2) and three equivalent F(3) atoms to form FeF6 octahedra that share corners with three equivalent Fe(1)F6 octahedra, faces with three equivalent Rb(1)F12 cuboctahedra, and faces with three equivalent Ba(1)F12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. There are three inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to one Rb(1), one Ba(1), two equivalent Ba(2), and one Fe(1) atom. In the second F site, F(2) is bonded in a 5-coordinate geometry to two equivalent Rb(1), one Ba(1), one Ba(2), and one Fe(2) atom. In the third F site, F(3) is bonded in a distorted linear geometry to one Rb(1), one Ba(2), two equivalent Ba(1), one Fe(1), and one Fe(2) atom. is represented by the CIF card [CIF]
data_RbBa2Fe2F9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.857
_cell_length_b   7.857
_cell_length_c   7.857
_cell_angle_alpha   44.833
_cell_angle_beta   44.833
_cell_angle_gamma   44.833
_symmetry_Int_Tables_number   1
_cell_volume   219.357
_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
  Rb  Rb0  1  0.213  0.213  0.213  1.0
  Ba  Ba1  1  0.999  0.999  0.999  1.0
  Ba  Ba2  1  0.793  0.793  0.793  1.0
  Fe  Fe3  1  0.392  0.392  0.392  1.0
  Fe  Fe4  1  0.604  0.604  0.604  1.0
  F  F5  1  0.266  0.782  0.266  1.0
  F  F6  1  0.782  0.266  0.266  1.0
  F  F7  1  0.266  0.266  0.782  1.0
  F  F8  1  0.735  0.210  0.735  1.0
  F  F9  1  0.210  0.735  0.735  1.0
  F  F10  1  0.735  0.735  0.210  1.0
  F  F11  1  0.993  0.506  0.506  1.0
  F  F12  1  0.506  0.506  0.993  1.0
  F  F13  1  0.506  0.993  0.506  1.0
[/CIF]
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