Condensed Aromatics. Part II The Five-Parameter Approximation of the In-Plane Force Field of Molecular Vibrations

Abstract

Abstract An approximate force field for the in-plane vibrations of condensed aromatics with only five parameters is investigated. Calculated frequencies are given for naphthalene, anthracene and coronene. The results are compared with values from other, more elaborate methods, mainly the Califano-Neto force field. The five-parameter approximation is found to be useful as an aid in assignments of experimental frequencies. It appears to give amazingly good results considering its great simplicity and small number of parameters. New experimental infrared and Raman data for anthracene and coronene are given. Especially some new features in the Raman spectrum of anthracene are reported in some details.