data_NaBr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.25
_cell_length_b   5.25
_cell_length_c   4.21
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaBr
_chemical_formula_sum   'Na2 Br2'
_cell_volume   116.14
_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  Na2  1  0.63  0.63  0.0  1.0
  Na  Na3  1  0.0  0.0  0.0  1.0
  Br  Br0  1  0.63  0.0  0.21  1.0
  Br  Br1  1  0.0  0.63  1.0  1.0

data_NaBr
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.43
_cell_length_b   7.43
_cell_length_c   4.21
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   NaBr
_chemical_formula_sum   'Na4 Br4'
_cell_volume   232.28
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  0.31  0.31  0.0  1.0
  Br  Br1  2  0.0  0.0  1.0  1.0
  Br  Br2  2  0.13  0.5  0.21  1.0

Na Na Br Br