Push−pull organic molecules that combine a polyfunctionalized electron-donating carbazole
moiety with a new acceptor group, 4-methylene-4H-oxazol-5-ones, were synthesized and
characterized as nonlinear optical chromophores with promising μβ values. First-order
hyperpolarizability and dipole moments were calculated by MNDO, AM1 and PM3 methods.
Theoretical μβ values were compared to experimental data measured in solution by electric-field-induced second-harmonic generation (EFISH). The different factors that could influence
the NLO response, especially the gain or loss of aromatization stabilization during the charge-transfer process, were studied. The thermal stability of these new chromophores is also
reported.