data_[Na4Ni2H8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Ni  1.9100  1.3500  0.7400
  H  2.2000  0.2500  0.0000
]
_symmetry_space_group_name_H-M [Cmmm]
_cell_length_a [3.4185]
_cell_length_b [14.1367]
_cell_length_c [3.3912]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [65]
_chemical_formula_structural [Na2NiH4]
_chemical_formula_sum '[Na4 Ni2 H8]'
_cell_volume [163.8869]
_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
[
  Na  Na0  4  0.0000  0.3812  0.5000  1
  Ni  Ni1  2  0.0000  0.0000  0.0000  1
  H  H2  4  0.0000  0.1127  0.0000  1
  H  H3  2  0.0000  0.0000  0.5000  1
  H  H4  2  0.0000  0.5000  0.0000  1
]