General model for the description of the third-order optical nonlinearities in conjugated systems: Application to the all-trans beta-carotene molecule
Abbreviated Journal Title
Phys. Rev. B
NITRO-STILBENE DANS; 3RD-HARMONIC GENERATION; 2-PHOTON ABSORPTION; ELECTRONIC EXCITATIONS; 2ND HYPERPOLARIZABILITY; INTERCHAIN DISPERSION; RELAXATION ENERGIES; RAMAN EXCITATION; POLYMERS; POLYENES; Physics, Condensed Matter
On the basis of an extended configuration-interaction description of the lowest singlet excited states, we investigate the third-order nonlinear optical response of the beta-carotene molecule by means of the sum-overstates approach. We first uncover the nature of the electronic states contributing primarily to the cubic molecular polarizabilities. From this starting point, we apply a simplified model to evaluate the frequency-dependent third-harmonic generation (THG) and electroabsorption (EA) spectra; the vibronic structure of the spectra is described by taking into account Franck-Condon factors calculated in a displaced oscillator model. For both the THG and EA processes, we obtain good agreement between the theoretical simulations and the experimental data, which underlines the general character of our model.
Physical Review B
"General model for the description of the third-order optical nonlinearities in conjugated systems: Application to the all-trans beta-carotene molecule" (1997). Faculty Bibliography 1990s. 1843.