Ultrafast nonlinear optical studies of cyclo[4]naphthobipyrroles

摘要: Expanded porphyrins belong to the class of porphyrinoids, where core porphyrin macrocycle is increased either by incorporating additional pyrrolic units, or increasing number bridging carbon atoms from more than four, a combination both. The significance these classes compounds lies in their novel photophysical and nonlinear optical properties. Superior nonlinear coefficients are usually observed for aromatic expanded porphyrins with large π-electrons owing distinct structural features. In this regard, cyclo[8]pyrrole is unique, its planar 30-π macrocyclic ring diprotonated state. Here, all eight pyrrole units are directly linked each other through a-positions. Recently, we have synthesized, cyclo[4]naphthobipyrroles, a unique cyclo[8]pyrroles, alternate fused naphthalene moieties. This adds more rigidity resultant while further extending π-conjugation. Herein, present some of our results picosecond studies â-octa-isopropyl-cyclo[4]naphthobipyrrole. nonlinear optical were extracted Z-scan measurements. values two-photon cross-sections obtained for these molecules range 10 4 GM.