LABELING OF BENZENOID SYSTEMS WHICH REFLECTS THE VERTEX-DISTANCE RELATIONS

It is shown that the vertices of benzenoid systems admit a labeling wh ich reflects their distance relations. To every vertex of a molecular graph of a benzenoid hydrocarbon a sequence of zeros and ones (a binar y number) can be associated, such that the number of positions in whic h these sequences differ is equal to the graph-theoretic vertex distan ce. It is shown by an example that such labelings can be used not only for nomenclature purposes but also for fast evaluation of molecular p arameters based on the graph distance.