The material described by RbTl(FeSe)8 crystallizes in the tetragonal I-4m2 space group. Rb(1) is bonded in a body-centered cubic geometry to four equivalent Se(2) and four equivalent Se(3) atoms. Fe(1) is bonded in a 4-coordinate geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. Tl(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to four equivalent Fe(1) and two equivalent Tl(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Rb(1) and four equivalent Fe(1) atoms to form a mixture of distorted corner and edge-sharing SeRb2Fe4 pentagonal pyramids. In the third Se site, Se(3) is bonded to two equivalent Rb(1) and four equivalent Fe(1) atoms to form a mixture of distorted corner and edge-sharing SeRb2Fe4 pentagonal pyramids. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to four equivalent Fe(1) and two equivalent Tl(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbTl(FeSe)8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.264
_cell_length_b   16.264
_cell_length_c   16.264
_cell_angle_alpha   161.852
_cell_angle_beta   161.852
_cell_angle_gamma   25.775
_symmetry_Int_Tables_number   1
_cell_volume   417.217
_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  0.250  0.750  0.500  1.0
  Tl  Tl1  1  0.000  0.000  0.000  1.0
  Fe  Fe2  1  0.874  0.874  0.500  1.0
  Fe  Fe3  1  0.126  0.627  1.000  1.0
  Fe  Fe4  1  0.627  0.126  0.000  1.0
  Fe  Fe5  1  0.373  0.373  0.500  1.0
  Fe  Fe6  1  0.373  0.874  0.000  1.0
  Fe  Fe7  1  0.627  0.627  0.500  1.0
  Fe  Fe8  1  0.126  0.126  0.500  1.0
  Fe  Fe9  1  0.874  0.373  1.000  1.0
  Se  Se10  1  0.572  0.072  0.500  1.0
  Se  Se11  1  0.825  0.825  0.000  1.0
  Se  Se12  1  0.325  0.325  0.000  1.0
  Se  Se13  1  0.072  0.572  0.500  1.0
  Se  Se14  1  0.675  0.675  0.000  1.0
  Se  Se15  1  0.928  0.428  0.500  1.0
  Se  Se16  1  0.428  0.928  0.500  1.0
  Se  Se17  1  0.175  0.175  0.000  1.0
[/CIF]
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The material described by RbTl(FeSe)8 crystallizes in the tetragonal I-4m2 space group. Rb(1) is bonded in a body-centered cubic geometry to four equivalent Se(2) and four equivalent Se(3) atoms. Fe(1) is bonded in a 4-coordinate geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. Tl(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to four equivalent Fe(1) and two equivalent Tl(1) atoms. In the second Se site, Se(2) is bonded to two equivalent Rb(1) and four equivalent Fe(1) atoms to form a mixture of distorted corner and edge-sharing SeRb2Fe4 pentagonal pyramids. In the third Se site, Se(3) is bonded to two equivalent Rb(1) and four equivalent Fe(1) atoms to form a mixture of distorted corner and edge-sharing SeRb2Fe4 pentagonal pyramids. In the fourth Se site, Se(4) is bonded in a 4-coordinate geometry to four equivalent Fe(1) and two equivalent Tl(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbTl(FeSe)8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.264
_cell_length_b   16.264
_cell_length_c   16.264
_cell_angle_alpha   161.852
_cell_angle_beta   161.852
_cell_angle_gamma   25.775
_symmetry_Int_Tables_number   1
_cell_volume   417.217
_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  0.250  0.750  0.500  1.0
  Tl  Tl1  1  0.000  0.000  0.000  1.0
  Fe  Fe2  1  0.874  0.874  0.500  1.0
  Fe  Fe3  1  0.126  0.627  1.000  1.0
  Fe  Fe4  1  0.627  0.126  0.000  1.0
  Fe  Fe5  1  0.373  0.373  0.500  1.0
  Fe  Fe6  1  0.373  0.874  0.000  1.0
  Fe  Fe7  1  0.627  0.627  0.500  1.0
  Fe  Fe8  1  0.126  0.126  0.500  1.0
  Fe  Fe9  1  0.874  0.373  1.000  1.0
  Se  Se10  1  0.572  0.072  0.500  1.0
  Se  Se11  1  0.825  0.825  0.000  1.0
  Se  Se12  1  0.325  0.325  0.000  1.0
  Se  Se13  1  0.072  0.572  0.500  1.0
  Se  Se14  1  0.675  0.675  0.000  1.0
  Se  Se15  1  0.928  0.428  0.500  1.0
  Se  Se16  1  0.428  0.928  0.500  1.0
  Se  Se17  1  0.175  0.175  0.000  1.0
[/CIF]
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