Abstract
A fundamental limit of π-conjugation seems to dictate the maximum nonlinear optical (NLO) response of fluorene-based “push–pull” (D−π–A) chromophores SPH1–SPH5 and the precursor aldehyde 4. Comparison of the first hyperpolarizability (βHRS) and intrinsic first hyperpolarizability (βint) values of the fluorene-based chromophores having different lengths and/or pathways of π-conjugation between donor and acceptor units, measured using the hyper-Rayleigh scattering (HRS) technique, revealed that the extension of π-conjugation beyond the limit (the horizontal limit!) does not necessarily improve the NLO response, which is determined by the combined influence of red shift of the intramolecular charge transfer (ICT) bands, optical band gap, and dipole moment of these chromophores. Additionally, the spatial distance between the donor and the acceptor units also constitutes an important attribute influencing the βHRS.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
