Knowledge Bank

It was shown that the strong absorption band observed with some molecules containing electron donating and accepting groups can be explained by the simple treatment and can be regarded as the intramolecular charge transfer $absorption.1$ The same method was applied to explain the difference between the absorption spectrum of p-disubstituted benzene molecule and that of o-, m-disubstituted one. Furthermore, on the basis of the result obtained by the improved treatment, the accuracy of our method will be discussed.