code: public void addAtom(IPDBAtom oAtom, IMonomer oMonomer) {
          super.addAtom(oAtom, oMonomer);
          if (!sequentialListOfMonomers.contains(oMonomer.getMonomerName()))
              sequentialListOfMonomers.add(oMonomer.getMonomerName());
      }
docs: Adds the atom oAtom to a specified Monomer. Additionally, it keeps
  record of the iCode.
  
  @param oAtom  The IPDBAtom to add
  @param oMonomer  The monomer the atom belongs to