The material structure described by KBa3(FeAs)8 crystallizes in the triclinic P-1 space group. K(1) is bonded in a body-centered cubic geometry to two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a body-centered cubic geometry to two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. In the second Ba site, Ba(2) is bonded in a body-centered cubic geometry to two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one As(2), one As(3), and two equivalent As(1) atoms to form a mixture of edge and corner-sharing FeAs4 tetrahedra. In the second Fe site, Fe(2) is bonded to one As(1), one As(4), and two equivalent As(2) atoms to form a mixture of edge and corner-sharing FeAs4 tetrahedra. In the third Fe site, Fe(3) is bonded to one As(2), one As(4), and two equivalent As(3) atoms to form a mixture of edge and corner-sharing FeAs4 tetrahedra. In the fourth Fe site, Fe(4) is bonded to one As(1), one As(3), and two equivalent As(4) atoms to form a mixture of edge and corner-sharing FeAs4 tetrahedra. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to one K(1), one Ba(2), two equivalent Ba(1), one Fe(2), one Fe(4), and two equivalent Fe(1) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to one K(1), one Ba(2), two equivalent Ba(1), one Fe(1), one Fe(3), and two equivalent Fe(2) atoms. In the third As site, As(3) is bonded in a 8-coordinate geometry to one K(1), one Ba(2), two equivalent Ba(1), one Fe(1), one Fe(4), and two equivalent Fe(3) atoms. In the fourth As site, As(4) is bonded in a 8-coordinate geometry to one K(1), one Ba(2), two equivalent Ba(1), one Fe(2), one Fe(3), and two equivalent Fe(4) atoms. is represented by the CIF file [CIF]
data_KBa3(FeAs)8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.162
_cell_length_b   8.720
_cell_length_c   7.859
_cell_angle_alpha   64.326
_cell_angle_beta   73.726
_cell_angle_gamma   97.221
_symmetry_Int_Tables_number   1
_cell_volume   406.936
_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
  K  K0  1  0.000  0.000  0.000  1.0
  Ba  Ba1  1  1.000  0.494  0.753  1.0
  Ba  Ba2  1  0.000  0.000  0.500  1.0
  Ba  Ba3  1  0.000  0.506  0.247  1.0
  Fe  Fe4  1  0.500  0.625  0.313  1.0
  Fe  Fe5  1  0.501  0.625  0.814  1.0
  Fe  Fe6  1  0.500  0.125  0.062  1.0
  Fe  Fe7  1  0.500  0.125  0.562  1.0
  Fe  Fe8  1  0.500  0.375  0.687  1.0
  Fe  Fe9  1  0.499  0.375  0.186  1.0
  Fe  Fe10  1  0.500  0.875  0.438  1.0
  Fe  Fe11  1  0.500  0.875  0.938  1.0
  As  As12  1  0.303  0.327  0.510  1.0
  As  As13  1  0.302  0.328  0.011  1.0
  As  As14  1  0.301  0.824  0.264  1.0
  As  As15  1  0.301  0.824  0.763  1.0
  As  As16  1  0.697  0.673  0.490  1.0
  As  As17  1  0.698  0.672  0.989  1.0
  As  As18  1  0.699  0.176  0.237  1.0
  As  As19  1  0.699  0.176  0.736  1.0
[/CIF]
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The material structure described by KBa3(FeAs)8 crystallizes in the triclinic P-1 space group. K(1) is bonded in a body-centered cubic geometry to two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a body-centered cubic geometry to two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. In the second Ba site, Ba(2) is bonded in a body-centered cubic geometry to two equivalent As(1), two equivalent As(2), two equivalent As(3), and two equivalent As(4) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one As(2), one As(3), and two equivalent As(1) atoms to form a mixture of edge and corner-sharing FeAs4 tetrahedra. In the second Fe site, Fe(2) is bonded to one As(1), one As(4), and two equivalent As(2) atoms to form a mixture of edge and corner-sharing FeAs4 tetrahedra. In the third Fe site, Fe(3) is bonded to one As(2), one As(4), and two equivalent As(3) atoms to form a mixture of edge and corner-sharing FeAs4 tetrahedra. In the fourth Fe site, Fe(4) is bonded to one As(1), one As(3), and two equivalent As(4) atoms to form a mixture of edge and corner-sharing FeAs4 tetrahedra. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 8-coordinate geometry to one K(1), one Ba(2), two equivalent Ba(1), one Fe(2), one Fe(4), and two equivalent Fe(1) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to one K(1), one Ba(2), two equivalent Ba(1), one Fe(1), one Fe(3), and two equivalent Fe(2) atoms. In the third As site, As(3) is bonded in a 8-coordinate geometry to one K(1), one Ba(2), two equivalent Ba(1), one Fe(1), one Fe(4), and two equivalent Fe(3) atoms. In the fourth As site, As(4) is bonded in a 8-coordinate geometry to one K(1), one Ba(2), two equivalent Ba(1), one Fe(2), one Fe(3), and two equivalent Fe(4) atoms. is represented by the CIF file [CIF]
data_KBa3(FeAs)8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.162
_cell_length_b   8.720
_cell_length_c   7.859
_cell_angle_alpha   64.326
_cell_angle_beta   73.726
_cell_angle_gamma   97.221
_symmetry_Int_Tables_number   1
_cell_volume   406.936
_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
  K  K0  1  0.000  0.000  0.000  1.0
  Ba  Ba1  1  1.000  0.494  0.753  1.0
  Ba  Ba2  1  0.000  0.000  0.500  1.0
  Ba  Ba3  1  0.000  0.506  0.247  1.0
  Fe  Fe4  1  0.500  0.625  0.313  1.0
  Fe  Fe5  1  0.501  0.625  0.814  1.0
  Fe  Fe6  1  0.500  0.125  0.062  1.0
  Fe  Fe7  1  0.500  0.125  0.562  1.0
  Fe  Fe8  1  0.500  0.375  0.687  1.0
  Fe  Fe9  1  0.499  0.375  0.186  1.0
  Fe  Fe10  1  0.500  0.875  0.438  1.0
  Fe  Fe11  1  0.500  0.875  0.938  1.0
  As  As12  1  0.303  0.327  0.510  1.0
  As  As13  1  0.302  0.328  0.011  1.0
  As  As14  1  0.301  0.824  0.264  1.0
  As  As15  1  0.301  0.824  0.763  1.0
  As  As16  1  0.697  0.673  0.490  1.0
  As  As17  1  0.698  0.672  0.989  1.0
  As  As18  1  0.699  0.176  0.237  1.0
  As  As19  1  0.699  0.176  0.736  1.0
[/CIF]
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