ABSTRACT
To date, very extensive use has been made of Pôlya’s Theorem for the enumeration of many different types of isomers. Examples include isotopic isomers [8 8 ], cycloalkanes [89], substituted porphyrins [90], polycyclic aromatic hydrocarbons [91], and inorganic complexes [92]. Further details on applications of the theorem in the chemical context are to be found in the review of Rouvray [73], in the monographs of Balaban [63] and Ttinajstid [62], and in a chapter by Balaban elsewhere in this volume. More recently developed techniques for isomer enumeration, such as the use of power groups by De Bruijn [93], the double coset formalism of Ruch [94], or the reformation of Pôlya’s Theorem using generalized wreath products by Balasubramanian [95], are discussed in some detail in the chapter by Balaban alluded to above in this volume of Mathematical Chemistry.
