The effect of fluorine atoms on the second-order optical nonlinear response of 4-nitro-4'-methoxy-trans-stilbene and polyene derivs. contg. up to three double bonds (n = 1, 2, 3) has been investigated within a semiempirical context (PM3 Hamiltonian). Exptl. data reported in literature indicate a βvec(SHG) value of 34, 47 and 76 (× 10-30 esu) for n = 1, 2, 3, resp., at 0.65 eV in CHCl3 solns. Our calcns. show that fluorinating the nitrophenyl group the βvec(SHG) is doubled. Further increase in the second-order nonlinear response can be obtained fluorinating the C:C bond linkers between the arom. moieties.Besides, the effect of different donor-acceptor pairs has been studied and the results interpreted in the two-state model context.Some results concerning the third-harmonic generation (THG), γ (THG), are presented, and a possible interpretation proposed. [on SciFinder(R)]
Effects of fluorine atoms on the optical nonlinear response of stilbene derivatives.
LELJ GAROLLA DI BARD, Francesco
2004-01-01
Abstract
The effect of fluorine atoms on the second-order optical nonlinear response of 4-nitro-4'-methoxy-trans-stilbene and polyene derivs. contg. up to three double bonds (n = 1, 2, 3) has been investigated within a semiempirical context (PM3 Hamiltonian). Exptl. data reported in literature indicate a βvec(SHG) value of 34, 47 and 76 (× 10-30 esu) for n = 1, 2, 3, resp., at 0.65 eV in CHCl3 solns. Our calcns. show that fluorinating the nitrophenyl group the βvec(SHG) is doubled. Further increase in the second-order nonlinear response can be obtained fluorinating the C:C bond linkers between the arom. moieties.Besides, the effect of different donor-acceptor pairs has been studied and the results interpreted in the two-state model context.Some results concerning the third-harmonic generation (THG), γ (THG), are presented, and a possible interpretation proposed. [on SciFinder(R)]I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.