Novel 1,10-phenanthroline-containing Ï-conjugated chromophores with varied electron donors were synthesized and characterized together with their corresponding nickel(II) chelated complexes. The linear absorption maxima for these chromophores could be tuned from 357 to 415 nm by using different electron donors. The 1,10-phenanthroline-containing Ï-conjugated chromophores exhibit strong fluorescence in solutions upon one- or two-photon excitation. The fluorescence of these chromophores can be quenched or partially quenched by some metal ions due to an excellent metal ion chelating ability of the 1,10-phenanthroline backbone. The nickel(II) chelating complexes show quenched emission, both in dilute and concentrated solutions, compared to their metal ion-free chromophores. Their two-photon absorption (TPA) spectra are obtained using a newly developed multi-photon spectroscopic technique which utilizes a single strong femtosecond white-light continuum generation beam. The two-photon absorption spectra show that the TPA band for these compounds can be tuned by choosing different electron donors. The maximum TPA cross-section Ï2 values for the three metal ion-free chromophores are variable from 0.58 to 2.26 Ã 10â20 cm4 GWâ1
(±15%). The metal ion-free chromophore-containing dihexylamino groups (9c) has a larger TPA cross-section Ï2 value compared to the chromophores containing alkyloxy groups or alkylthio groups. When the metal ion-free chromophores coordinate with the nickel(II) ion, the resulting complexes do not lose their excellent two-photon-absorbing ability. The nickel(II) chelated complexes display red-shifted two-photon absorption bands compared with their metal ion-free chromophores.
合成并表征了含有1,10-
菲啰啉的π-共轭色素,具有不同的电子供体及其相应的
镍(II)配位复合物。这些色素的线性吸收峰值可以通过使用不同的电子供体进行调节,从357 nm到415 nm。这些含1,10-
菲啰啉的π-共轭色素在单光子或双光子激发下表现出强烈的荧光。由于1,10-
菲啰啉骨架具有优良的
金属离子螯合能力,这些色素的荧光可以被某些
金属离子淬灭或部分淬灭。与无
金属离子的色素相比,
镍(II)螯合复合物在稀溶液和浓溶液中均显示出淬灭的发射。它们的双光子吸收(
TPA)光谱采用新开发的多光子光谱技术获得,该技术利用单一强的飞秒白光连续辐射束。双光子吸收光谱显示这些化合物的
TPA带可以通过选择不同的电子供体进行调节。三种无
金属离子的色素的最大
TPA截面σ₂值在0.58到2.26 × 10⁻²⁰ cm⁴ GW⁻¹(±15%)范围内变化。含有二己基
氨基基团的无
金属离子色素(9c)的
TPA截面σ₂值大于含有烷氧基或烷
硫基的色素。当无
金属离子色素与
镍(II)离子配位时,得到的复合物仍保持其优良的双光子吸收能力。与无
金属离子的色素相比,
镍(II)螯合复合物显示出红移的双光子吸收带。