data_BeCu2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.34
_cell_length_b   4.34
_cell_length_c   4.34
_cell_angle_alpha   131.2
_cell_angle_beta   131.2
_cell_angle_gamma   71.49
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BeCu2Si
_chemical_formula_sum   'Be1 Cu2 Si1'
_cell_volume   45.35
_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
  Be  Be0  1  0.0  0.0  0.0  1.0
  Cu  Cu1  1  0.79  0.0  0.76  1.0
  Cu  Cu2  1  0.0  0.79  0.76  1.0
  Si  Si3  1  0.0  0.0  0.52  1.0

data_BeCu2Si
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.07
_cell_length_b   5.07
_cell_length_c   4.34
_cell_angle_alpha   90.0
_cell_angle_beta   125.74
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   BeCu2Si
_chemical_formula_sum   'Be2 Cu4 Si2'
_cell_volume   90.71
_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
  Be  Be0  2  0.0  0.0  0.0  1.0
  Cu  Cu1  4  0.13  0.1  0.03  1.0
  Si  Si2  2  0.48  0.0  0.48  1.0

Be Cu Cu Si
Be Cu Cu Si 0 1 - o - 0 2 o - - 0 3 o o - 1 3 + o o 2 3 o + o 