data_[K2Fe2As2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  K  0.8200  2.2000  1.5200
  Fe  1.8300  1.4000  0.8525
  As  2.1800  1.1500  0.6600
]
_symmetry_space_group_name_H-M [P4/nmm]
_cell_length_a [3.9293]
_cell_length_b [3.9293]
_cell_length_c [10.5819]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [129]
_chemical_formula_structural [KFeAs]
_chemical_formula_sum '[K2 Fe2 As2]'
_cell_volume [163.3788]
_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
[
  K  K0  2  0.0000  0.5000  0.2891  1.0
  Fe  Fe1  2  0.0000  0.0000  0.0000  1.0
  As  As2  2  0.0000  0.5000  0.8816  1.0
]