ABSTRACT
In the present article a graph-theoretical analysis of the simplest variant of molecular orbital theory [1], i.e. Huckel theory [2], will be given. Notwithstanding its naivety and shortcominp [3] Huckel theory is still extensively used in theoretical organic chemistry [4] in its various modifications [5]. This illustrates that quantum-chemical theories cannot be unconditionally judged as rither good or bad, for much depends on the system under consideration, which of its physical, chemical, or biological properties are studied, and which approximation is used [6-10]. For these reasons, the theory which ^ves the greatest insight into a given chemical problem should be selected for use, bearing in mind that a qualitative rule covering a wide range of data is far better than a highly quantitative result which produces no general trends [11].
