Electric field induced second harmonic generation/third harmonic generation measurements on molecules with extended charge transfer: Absorption domain and strong resonance effects

Abstract

An enlarged method of performing electric field induced second harmonic generation (EFISHG) or third harmonic generation (THG) measurements of molecular hyperpolarizabilities in the strongly resonant regime is proposed. The influence of absorption coefficients and anomalous dispersion are discussed in detail and corrections proposed which require no change in the experimental setup. An alternative method of data interpretation is presented and its validity discussed for two examples of molecular structures.