Physical Methods in Heterocyclic Chemistry, Volume III provides information pertinent to ionization constants and ultraviolet spectra. This book discusses the methods for the prediction of ionization constants. Comprised of seven chapters, this volume starts with an overview of the ionization constants of a number of heterocyclic compounds. This text then describes the procedures that are usually followed when molecular structure determinations based on electron diffraction measurements are carried out. Other chapters consider the concept of group frequencies, which rests upon the experimental fact that certain groups of atom give rise to vibrational transitions which are close or at the same frequency irrespective of the particular molecule in which the group occurs. The final chapter deals with the optical rotatory power, which is the only generally accessible physical property by which enantiomers can be distinguished in isolation. Heterocyclic chemists, biochemists, molecular biologists, and researchers will find this book extremely useful.