Enumeration

By enumeration of benzenoid systems, the counting of all possible non-isomorphic members within a class of benzenoids is understood. Usually, but not always, the number of hexagons (h) is the leading parameter. Thus the enumeration for h = 1,2, 3, 4, etc. is to be executed. Figure 2.1 shows the results of enumerations for h = 2,3, and 4, which account for all possible benzenoid systems with these numbers of hexagons. For larger h values, it is of interest to subdivide the total amount of benzenoids into different classes. In this connection we speak about classification.