First order molecular hyperpolarizabilities and intramolecular charge transfer from the vibrational spectra of NLO material: ethyl-3-(3, 4-dihydroxyphenyl)-2-propenoate
Abstract
As part of the efforts for the design of new organic nonlinear optical (NLO) materials with high efficiency for present day technological requirements, a comprehensive investigation on the intramolecular charge transfer (CT) of an efficient pi-conjugated potential push-pull NLO chromophore, ethyl-3-(3,4-dihydroxyphenyl)-2-propenoate(EDP) to a strong electron-acceptor group through the pi-conjugated bridge has been carried out from their vibrational spectra. The first hyperpolarizabilities are investigated by ab initio method.
The NLO efficiency is experimentally measured by powder efficiency experiment. The strongest vibrational modes contributing to the electro-optic effect from the simultaneous infrared (IR) and Raman activities have been identified and analyzed unambiguously.
The influence of electronic effects, hyperconjugation and backdonation, on the C-H stretching vibrations been extensively investigated.