data_Na2BeHg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.39
_cell_length_b   3.39
_cell_length_c   8.4
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2BeHg
_chemical_formula_sum   'Na2 Be1 Hg1'
_cell_volume   96.74
_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  Na2  1  0.0  0.0  0.95  1.0
  Na  Na3  1  0.7  0.7  0.52  1.0
  Be  Be0  1  0.0  0.0  0.93  1.0
  Hg  Hg1  1  0.7  0.7  0.6  1.0

data_Na2BeHg
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.8
_cell_length_b   4.8
_cell_length_c   8.4
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Na2BeHg
_chemical_formula_sum   'Na4 Be2 Hg2'
_cell_volume   193.49
_cell_formula_units_Z   2
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  2  0.0  0.0  0.95  1.0
  Na  Na1  2  0.2  0.5  0.52  1.0
  Be  Be2  2  0.0  0.0  0.93  1.0
  Hg  Hg3  2  0.2  0.5  0.6  1.0

Na Na Be Hg
Na Na Be Hg 0 2 o o o 1 3 o o o 