The material structure described by CsFeF4 crystallizes in the tetragonal P4/nmm space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 12-coordinate geometry to four equivalent F(2) and eight equivalent F(1) atoms. In the second Cs site, Cs(2) is bonded in a 12-coordinate geometry to four equivalent F(2) and eight equivalent F(1) atoms. Fe(1) is bonded to two equivalent F(1) and four equivalent F(2) atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one Fe(1) atom. In the second F site, F(2) is bonded in a distorted bent 150 degrees geometry to one Cs(1), one Cs(2), and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_CsFeF4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.817
_cell_length_b   7.817
_cell_length_c   6.484
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   396.237
_cell_formula_units_Z   4
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
  Cs  Cs0  1  0.500  0.500  0.500  1.0
  Cs  Cs1  1  0.000  0.000  0.500  1.0
  Cs  Cs2  1  0.500  0.000  0.444  1.0
  Cs  Cs3  1  0.000  0.500  0.556  1.0
  Fe  Fe4  1  0.250  0.750  0.000  1.0
  Fe  Fe5  1  0.250  0.250  0.000  1.0
  Fe  Fe6  1  0.750  0.750  0.000  1.0
  Fe  Fe7  1  0.750  0.250  0.000  1.0
  F  F8  1  0.720  0.220  0.715  1.0
  F  F9  1  0.280  0.780  0.715  1.0
  F  F10  1  0.280  0.220  0.715  1.0
  F  F11  1  0.720  0.780  0.715  1.0
  F  F12  1  0.220  0.720  0.285  1.0
  F  F13  1  0.220  0.280  0.285  1.0
  F  F14  1  0.780  0.720  0.285  1.0
  F  F15  1  0.780  0.280  0.285  1.0
  F  F16  1  0.747  0.500  0.951  1.0
  F  F17  1  0.000  0.753  0.951  1.0
  F  F18  1  0.000  0.247  0.951  1.0
  F  F19  1  0.253  0.500  0.951  1.0
  F  F20  1  0.753  0.000  0.049  1.0
  F  F21  1  0.247  0.000  0.049  1.0
  F  F22  1  0.500  0.747  0.049  1.0
  F  F23  1  0.500  0.253  0.049  1.0
[/CIF]
.
The material structure described by CsFeF4 crystallizes in the tetragonal P4/nmm space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 12-coordinate geometry to four equivalent F(2) and eight equivalent F(1) atoms. In the second Cs site, Cs(2) is bonded in a 12-coordinate geometry to four equivalent F(2) and eight equivalent F(1) atoms. Fe(1) is bonded to two equivalent F(1) and four equivalent F(2) atoms to form corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one Fe(1) atom. In the second F site, F(2) is bonded in a distorted bent 150 degrees geometry to one Cs(1), one Cs(2), and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_CsFeF4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.817
_cell_length_b   7.817
_cell_length_c   6.484
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   396.237
_cell_formula_units_Z   4
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
  Cs  Cs0  1  0.500  0.500  0.500  1.0
  Cs  Cs1  1  0.000  0.000  0.500  1.0
  Cs  Cs2  1  0.500  0.000  0.444  1.0
  Cs  Cs3  1  0.000  0.500  0.556  1.0
  Fe  Fe4  1  0.250  0.750  0.000  1.0
  Fe  Fe5  1  0.250  0.250  0.000  1.0
  Fe  Fe6  1  0.750  0.750  0.000  1.0
  Fe  Fe7  1  0.750  0.250  0.000  1.0
  F  F8  1  0.720  0.220  0.715  1.0
  F  F9  1  0.280  0.780  0.715  1.0
  F  F10  1  0.280  0.220  0.715  1.0
  F  F11  1  0.720  0.780  0.715  1.0
  F  F12  1  0.220  0.720  0.285  1.0
  F  F13  1  0.220  0.280  0.285  1.0
  F  F14  1  0.780  0.720  0.285  1.0
  F  F15  1  0.780  0.280  0.285  1.0
  F  F16  1  0.747  0.500  0.951  1.0
  F  F17  1  0.000  0.753  0.951  1.0
  F  F18  1  0.000  0.247  0.951  1.0
  F  F19  1  0.253  0.500  0.951  1.0
  F  F20  1  0.753  0.000  0.049  1.0
  F  F21  1  0.247  0.000  0.049  1.0
  F  F22  1  0.500  0.747  0.049  1.0
  F  F23  1  0.500  0.253  0.049  1.0
[/CIF]
.