The effects of ligand substitution and deuteriation on the spectroscopic and photophysical properties of [Ru(LL)(CN)_4]^2− complexes
The effects of ligand substitution and deuteriation on the spectroscopic and photophysical properties of [Ru(LL)(CN)_4]^2− complexes
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配体取代和氘化对 [Ru(LL)(CN)_4]^2− 配合物光谱和光物理性质的影响
DOI：
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发表时间：
2007
影响因子：
3.1
通讯作者：
A. Horváth
中科院分区：
文献类型：
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作者：
Margit Kovács;K. Ronayne;W. Browne;W. Henry;J. Vos;J. McGarvey;A. Horváth
本文报道了一系列[Ru（LL）（CN）_4]^2−配合物及其甲基和苯基取代的衍生物和几种氘代同位素体的光谱特性。并与系列2，2 ′-联吡啶（bipy）衍生物及类似的[Ru（LL）_3]^2+配合物进行了光学和振动性质的比较。研究表明，在[Ru（LL）（CN）_4]^2-的最低能量^1MLCT吸收带中，给电子基团（CH_3）和吸电子基团（C_6H_5，COO^-）分别取代bipy的4，4 ′位和phen的4，7-位会引起明显的蓝移和红移。发现源自^3MLCT激发态的发射能量取决于芳环振动模式的性质以及取代基的供电子和/或吸电子性质。单模式Franck-Condon分析表明，甲基取代使两个系列（bipy和phen）的黄-里斯因子（S _M）显著增加，而苯基取代使S _M降低。由发光量子产率和寿命随温度的变化关系，估算了非辐射和辐射衰减到基态的速率（knr）和辐射衰减到基态的速率（kph），以及热激活失活途径的参数（A4 th，Δ E4 th和Add，Δ Edd）。它已被证明，非辐射衰减速率和温度依赖的衰减过程是更有效的联吡啶配合物比phen衍生物由于后者的配体的刚性。
The spectroscopic characterisation of a series of [Ru(LL)(CN)_4]^2− complexes, where LL = 1,10-phenanthroline (phen) and its methyl- and phenyl-substituted derivatives and several deuteriated isotopologues are reported. The optical and vibrational properties of these complexes are compared with that of the series of 2,2′-bipyridine (bipy) derivatives and analogous [Ru(LL)_3]^2+ complexes. It has been demonstrated that substitution at the 4,4′ positions of bipy and 4,7-positions of phen by electron donating (CH_3) and withdrawing (C_6H_5, COO^−) groups induces a pronounced blue and red shift, respectively, in the lowest energy ^1MLCT absorption band of [Ru(LL)(CN)_4]^2−. The energy of the emission originating from the ^3MLCT excited state is found to be dependant on the nature of the vibrational modes of the aromatic rings and the electron donating and/or withdrawing properties of the substituents. Single-mode Franck-Condon analysis indicates that methyl substitution leads to a significant increase in the Huang-Rhys factor ( S _M), while phenyl substitution results in a decrease in S _M for both series (bipy and phen) of complexes. The rate of non-radiative ( k _nr) and radiative decay ( k _ph) to the ground state and the parameters of thermally activated deactivation pathways ( A _4th, Δ E _4th and A _dd, Δ E _dd) were estimated from the temperature dependence of luminescence quantum yields and lifetimes. It has been demonstrated that the non-radiative decay rate and the temperature dependent decay processes are more efficient for bipy complexes than for phen derivatives due to the rigidity of the latter ligand.