def pdb_dict_to_data_dict(pdb_dict):
    """Converts an .pdb dictionary into an atomium data dictionary, with the
    same standard layout that the other file formats get converted into.

    :param dict pdb_dict: the .pdb dictionary.
    :rtype: ``dict``"""

    data_dict = {
     "description": {
      "code": None, "title": None, "deposition_date": None,
      "classification": None, "keywords": [], "authors": []
     }, "experiment": {
      "technique": None, "source_organism": None, "expression_system": None,
      "missing_residues": []
     }, "quality": {"resolution": None, "rvalue": None, "rfree": None},
      "geometry": {"assemblies": [], "crystallography": {}}, "models": []
    }
    update_description_dict(pdb_dict, data_dict)
    update_experiment_dict(pdb_dict, data_dict)
    update_quality_dict(pdb_dict, data_dict)
    update_geometry_dict(pdb_dict, data_dict)
    update_models_list(pdb_dict, data_dict)
    return data_dict