Author/Authors :
José-Luis and Ramos-Ortيz، نويسنده , , G. Ivan Maldonado، نويسنده , , J.L. and Hernلndez، نويسنده , , M.C.G. and Zolotukhin، نويسنده , , M.G. and Fomine، نويسنده , , S. and Frِhlich، نويسنده , , N. and Scherf، نويسنده , , U. and Galbrecht، نويسنده , , F. and Preis، نويسنده , , E. and Salmon، نويسنده , , M. and Cلrdenas، نويسنده , , J. and Chلvez، نويسنده , , M.I.، نويسنده ,
Abstract :
We designed and synthesized two novel fluorene monomers of D–A–D (donor–acceptor–donor) type (M1 and M2), and their two corresponding polymers (PM1 and PM2) and a copolymer (CPM). These high molecular weight, film-forming polymers were obtained from metal-free, superacid-catalyzed reactions of the monomers with N-phenylisatin. The cubic NLO response (χ(3)) for these new compounds, in solid thin films, was measured through the use of third-harmonic generation (THG) Maker-Fringes technique at IR wavelengths given values of the order of 10−12 esu from which, the corresponding second hyperpolarizabilities (γ) were estimated to be of the order of 10−33 esu for monomers and 10−31 esu for polymers. Second hyperpolarizabilities have also been estimated theoretically at B3LYP/6-31G(d) level of theory in gas phase and related with the electronic structure of the synthesized molecules.
