data_[Ca2H2O4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  H  2.2000  0.2500  0.0000
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [4.2952]
_cell_length_b [3.6285]
_cell_length_c [6.4012]
_cell_angle_alpha [90.0000]
_cell_angle_beta [107.8096]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [CaHO2]
_chemical_formula_sum '[Ca2 H2 O4]'
_cell_volume [94.9833]
_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
[
  Ca  Ca0  2  0.4026  0.7500  0.7336  1
  H  H1  2  0.0691  0.7500  0.0773  1
  O  O2  2  0.1634  0.2500  0.4685  1
  O  O3  2  0.2932  0.7500  0.0723  1
]