data_H2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.41
_cell_length_b   3.41
_cell_length_c   3.38
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   H2O
_chemical_formula_sum   'H4 O2'
_cell_volume   39.41
_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
  H  H0  1  0.15  0.15  0.11  1.0
  H  H1  1  0.26  0.26  0.11  1.0
  H  H2  1  0.86  0.56  0.8  1.0
  H  H3  1  0.56  0.86  0.8  1.0
  O  O4  1  0.0  0.0  0.02  1.0
  O  O5  1  0.71  0.71  0.71  1.0

data_H2O
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.83
_cell_length_b   4.83
_cell_length_c   3.38
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   H2O
_chemical_formula_sum   'H8 O4'
_cell_volume   78.81
_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
  H  H0  4  0.21  0.35  0.8  1.0
  H  H1  2  0.15  0.0  0.11  1.0
  H  H2  2  0.26  0.0  0.11  1.0
  O  O3  2  0.0  0.0  0.02  1.0
  O  O4  2  0.21  0.5  0.71  1.0

H H H H O O
H H H H O O 0 1 o o o 0 4 o o o 2 5 o o o 3 5 o o o 