Sun Wenfang, Wang Gang, Li Yunjing, Calvete Mario J F, Dini Danilo, Hanack Michael
Department of Chemistry, Biochemistry and Molecular Biology, North Dakota State University, Fargo, North Dakota 58105-5516, USA.
J Phys Chem A. 2007 May 3;111(17):3263-70. doi: 10.1021/jp071152k. Epub 2007 Apr 10.
Three axially substituted complexes, 2,3-octa(3,5-di-tert-butylphenoxy)-2,3-naphthalocyaninato indium chloride (1a), 2,3-octa(3,5-di-tert-butylphenoxy)-2,3-naphthalocyaninato indium bromide (1b), and 2,3-octa(3,5-di-tert-butylphenoxy)-2,3-naphthalocyaninato indium iodide (1c) have been synthesized and their photophysical properties have been investigated. Optical power limiting of nanosecond (ns) and picosecond (ps) laser pulses at 532 nm using these complexes has been demonstrated. All complexes display strong Q(0,0) absorption and measurable emission in the near-infrared region and exhibit strong excited-state absorption in the range of 470-700 nm upon ns laser excitation. The different axial ligands show negligible effect on the linear absorption, emission, and transient difference absorption spectra. However, the excited-state lifetime, triplet excited-state quantum yield, and efficiency to generate singlet oxygen are affected significantly by the heavier axial ligand. Brominated and iodinated complexes 1b and 1c show higher triplet excited-state quantum yield, while chlorinated complex 1a has longer excited-state lifetime and is more efficient in generating singlet oxygen. The iodinated complex 1c displayed the best optical limiting due to the higher ratio of excited-state absorption cross section to ground state absorption cross section (sigma(eff)/sigma(0)).
合成了三种轴向取代的配合物，即2,3-八(3,5-二叔丁基苯氧基)-2,3-萘酞菁铟氯化物(1a)、2,3-八(3,5-二叔丁基苯氧基)-2,3-萘酞菁铟溴化物(1b)和2,3-八(3,5-二叔丁基苯氧基)-2,3-萘酞菁铟碘化物(1c)，并对它们的光物理性质进行了研究。已证明使用这些配合物对532 nm的纳秒(ns)和皮秒(ps)激光脉冲具有光限幅作用。所有配合物在近红外区域均显示出强烈的Q(0,0)吸收和可测量的发射，并且在纳秒激光激发下在470-700 nm范围内表现出强烈的激发态吸收。不同的轴向配体对线性吸收、发射和瞬态差分吸收光谱的影响可忽略不计。然而，较重的轴向配体对激发态寿命、三重态激发态量子产率和单线态氧生成效率有显著影响。溴化和碘化配合物1b和1c显示出更高的三重态激发态量子产率，而氯化配合物1a具有更长的激发态寿命，并且在生成单线态氧方面更有效。由于激发态吸收截面与基态吸收截面的比值(sigma(eff)/sigma(0))较高，碘化配合物1c表现出最佳的光限幅性能。
