Dioxaborine- and Indole-Terminated Polymethines: Effects of Bridge Substitution on Absorption Spectra and Third-Order Polarizabilities
作者:Jonathan D. Matichak、Joel M. Hales、Stephen Barlow、Joseph W. Perry、Seth R. Marder
DOI:10.1021/jp110425r
日期:2011.3.24
Cyanine-like dyes are promising candidates for third-order nonlinear optical (NLO) applications such as all-optical switching. Here, we examine the consequences for linear and nonlinear optical properties of varying substituents on the central methine unit of bis(dioxaborine)-terminated anionic pentamethines and bis(indole)-terminated cationic heptamethines. The variation in absorption maxima and electrochemical
类花青染料是三阶非线性光学(NLO)应用(如全光学开关)的有前途的候选者。在这里,我们研究了在双(二氧茶碱)末端的阴离子五甲胺和双(吲哚)末端的阳离子七甲胺的中央次甲基单元上不同取代基的线性和非线性光学性质的后果。吸收最大值和电化学势随结构的变化通常可以使用Dewar-Knott规则来合理化,只要明确考虑了介观的和感应的电子撤离和捐赠。对于硝基和(二氧杂嘌呤基)乙烯基取代的双(二氧杂嘌呤)五甲胺,低能跃迁显着加宽,与11 H NMR谱表明偏离花青样几何形状。三阶极化率的实部和虚部Re(γ)和Im(γ)的测量值为1.3μm。Im(γ)的值表明Re(γ)的值显着共振增强,而硝基取代的二氧杂硼嘌呤实例中发现的Re(γ)的正值对于对称的聚次甲基来说是非典型的,并且表明两个国家待遇不足。讨论了这些结果与三阶NLO应用的生色团设计的相关性。