Absorption and second-harmonic generation of monomer and aggregate hemicyanine dye in Langmuir-Blodgett films.
Absorption and second-harmonic generation of monomer and aggregate hemicyanine dye in Langmuir-Blodgett films.
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Langmuir-Blodgett 薄膜中单体和聚集半花青染料的吸收和二次谐波产生。
作者：
J. Schildkraut;T. Penner;C. S. Willand;Abraham Ulman
本文报道了含半花菁染料的LB膜的吸收光谱和二次谐波产生。染料被发现是在H聚集体的形式在纯染料膜和大部分单体在1：4的染料花生酸膜。这一观察结果解释了文献中的一份报告，即混合染料-花生酸膜显示出比纯染料膜更高的二次谐波产生效率。它也可能是一个因素，在二次谐波产生的失败，以增加与非中心对称多层膜的层数的平方。
Absorption spectra and second-harmonic generation of Langmuir–Blodgett monolayers containing a hemicyanine dye with a large second-order hyperpolarizability are reported. The dye is found to be in the form of H aggregates in a pure-dye film and mostly monomeric in a 1:4 dye–arachidic acid film. This observation explains a report in the literature that mixed dye–arachidic acid films display greater second-harmonic generation efficiency than a pure-dye film. It may also be a factor in the reported failure of second-harmonic generation to increase quadratically with the number of layers in noncentrosymmetric multilayer films.