code: public static void setAtomProperties(IChemModel chemModel, Object propKey, Object propVal) {
          if (chemModel.getMoleculeSet() != null) {
              MoleculeSetManipulator.setAtomProperties(chemModel.getMoleculeSet(), propKey, propVal);
          }
          if (chemModel.getReactionSet() != null) {
              ReactionSetManipulator.setAtomProperties(chemModel.getReactionSet(), propKey, propVal);
          }
          if (chemModel.getCrystal() != null) {
              AtomContainerManipulator.setAtomProperties(chemModel.getCrystal(), propKey, propVal);
          }
      }
docs: Sets the AtomProperties of all Atoms inside an IChemModel.
  
  @param chemModel  The IChemModel object.
  @param propKey    The key of the property.
  @param propVal    The value of the property.