data_Na2FeSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.55
_cell_length_b   5.55
_cell_length_c   5.37
_cell_angle_alpha   99.23
_cell_angle_beta   99.23
_cell_angle_gamma   32.94
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2FeSi
_chemical_formula_sum   'Na2 Fe1 Si1'
_cell_volume   88.59
_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
  Na  Na1  1  0.75  0.0  0.32  1.0
  Na  Na2  1  0.99  0.0  0.98  1.0
  Fe  Fe0  1  0.87  0.0  0.65  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

data_Na2FeSi
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.14
_cell_length_b   5.37
_cell_length_c   5.55
_cell_angle_alpha   99.23
_cell_angle_beta   106.47
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2FeSi
_chemical_formula_sum   'Na2 Fe1 Si1'
_cell_volume   88.59
_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
  Na  Na0  1  0.0  0.32  0.75  1.0
  Na  Na1  1  0.0  0.98  0.99  1.0
  Fe  Fe2  1  0.0  0.65  0.87  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

Na Na Fe Si
Na Na Fe Si 0 2 o o o 1 3 + o + 1 2 o o o 2 3 + o + 