data_[Ac4H2Se4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ac  1.1000  1.9500  1.2600
  H  2.2000  0.2500  0.0000
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Immm]
_cell_length_a [4.2450]
_cell_length_b [6.1620]
_cell_length_c [12.2179]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [71]
_chemical_formula_structural [Ac2HSe2]
_chemical_formula_sum '[Ac4 H2 Se4]'
_cell_volume [319.5914]
_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
[
  Ac  Ac0  4  0.0000  0.5000  0.3421  1
  H  H1  2  0.0000  0.0000  0.0000  1
  Se  Se2  4  0.0000  0.0000  0.3375  1
]