Kumar Pawan, de Coene Yovan, Clays Koen, Kaur Paramjit, Singh Kamaljit
Department of Chemistry, UGC Centre of Advanced Study, Guru Nanak Dev University, Amritsar 143005, India.
Department of Chemistry, University of Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium.
Dalton Trans. 2023 Aug 29;52(34):12130-12142. doi: 10.1039/d3dt01897k.
The question of size economy in the design of chromophores for nonlinear optics is addressed in this investigation. We have synthesized directly linked donor-acceptor dyads, which lack a π-conjugated linker, the presence of which is usually considered obligatory in materials designed for nonlinear optics. Correlating linear optical data, electrochemical data, computational data and hyper Rayleigh scattering (HRS) data on ferrocene (Fc) based dyads, we demonstrate that the first hyperpolarizability of such size economical chromophores is significantly better compared to that of Fc based, traditional, larger, donor-π-acceptor chromophores. Arguably, a larger π-conjugated linker decreases the electronic communication between the donor and the acceptor and weakens the intramolecular charge transfer in such chromophores.
本研究探讨了用于非线性光学的发色团设计中的尺寸经济性问题。我们合成了直接相连的供体-受体二元体系，该体系缺少π共轭连接基团，而在设计用于非线性光学的材料中，π共轭连接基团的存在通常被认为是必不可少的。通过关联基于二茂铁（Fc）的二元体系的线性光学数据、电化学数据、计算数据和超瑞利散射（HRS）数据，我们证明，与基于Fc的传统的、更大的供体-π-受体发色团相比，这种尺寸经济的发色团的第一超极化率明显更好。可以说，更大的π共轭连接基团会降低供体与受体之间的电子通信，并削弱此类发色团中的分子内电荷转移。
