First- and second-order optical hyperpolarizabilities of polyaniline in solutions

Summary form only given. The class of materials known as conjugated polymers (CP) has attracted great attention due to its optical and semiconductor properties. Among CPs, polyaniline (PANI) has been found to be a unique material that presents a reversibility character of its conductivity. For example, upon redox and protonation it is possible to change the polymer from an insulating (leucoemeraldine) form, to a conducting polymer (emeraldine salt). Concerning its optical properties, PANI has been attracted interest because of its fast response time. Spectroscopic measurements have been performed of the first (/spl beta/) and second (/spl gamma/) hyperpolarizabilities of PANI dissolved in solutions of dimethyl sulfoxide (DMSO). We measured /spl beta/ and /spl gamma/ in various degrees of oxidation and protonation: emeraldine base (EB), emeraldine salt (ES), leucoemeraldine base (LB) and leucoemeraldine salt (LS). The spectroscopic techniques used to measure /spl beta/ and /spl gamma/ were hyper-Rayleigh scattering (HRS) and Z-scan, respectively.