code: @Override
      public Iterable<IAtom> atoms() {
          return new Iterable<IAtom>() {
  
              @Override
              public Iterator<IAtom> iterator() {
                  return new AtomsIterator();
              }
          };
      }
docs: Returns the Iterator to atoms making up this bond.
  Iterator.remove() is not implemented.
  
  @return An Iterator to atoms participating in this bond
  @see #setAtoms