data_BeHg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.49
_cell_length_b   6.49
_cell_length_c   6.49
_cell_angle_alpha   155.38
_cell_angle_beta   143.12
_cell_angle_gamma   44.84
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BeHg
_chemical_formula_sum   'Be2 Hg2'
_cell_volume   68.21
_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
  Be  Be0  1  0.38  0.97  0.91  1.0
  Be  Be1  1  0.0  0.08  0.1  1.0
  Hg  Hg2  1  0.0  0.03  0.65  1.0
  Hg  Hg3  1  0.38  0.03  0.35  1.0

data_BeHg
_symmetry_space_group_name_H-M   P-1
_cell_length_a   2.77
_cell_length_b   4.11
_cell_length_c   6.49
_cell_angle_alpha   108.44
_cell_angle_beta   102.31
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   BeHg
_chemical_formula_sum   'Be2 Hg2'
_cell_volume   68.21
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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
  Be  Be0  2  0.45  0.54  0.73  1.0
  Hg  Hg1  2  0.5  0.15  0.34  1.0

Be Be Hg Hg