data_Zr2SiSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.85
_cell_length_b   3.85
_cell_length_c   5.45
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Zr2SiSe
_chemical_formula_sum   'Zr2 Si1 Se1'
_cell_volume   80.63
_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
  Zr  Zr2  1  0.92  0.92  0.8  1.0
  Zr  Zr3  1  0.0  0.0  0.01  1.0
  Si  Si1  1  0.0  0.0  0.75  1.0
  Se  Se0  1  0.92  0.92  0.06  1.0

data_Zr2SiSe
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.44
_cell_length_b   5.44
_cell_length_c   5.45
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Zr2SiSe
_chemical_formula_sum   'Zr4 Si2 Se2'
_cell_volume   161.27
_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
  Zr  Zr0  2  0.0  0.0  0.01  1.0
  Zr  Zr1  2  0.42  0.5  0.8  1.0
  Si  Si2  2  0.0  0.0  0.75  1.0
  Se  Se3  2  0.42  0.5  0.06  1.0

Zr Zr Si Se
Zr Zr Si Se 0 2 + + o 1 3 - - o 