Avagyan Nane A, Lemport Pavel S, Polikovskiy Trofim A, Tsorieva Alisia V, Metlin Mikhail T, Taydakov Ilya V, Zonov Roman V, Lyssenko Konstantin A, Vokuev Mikhail F, Rodin Igor A, Tarasevich Boris N, Ustynyuk Yuri A, Nenajdenko Valentine G
Department of Chemistry, Lomonosov Moscow State University, Leninskie Gory 1 bld. 3, 119991, Moscow, Russia.
P.N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninskiy Prospekt, 119991 Moscow, Russia.
Dalton Trans. 2024 Aug 27;53(34):14469-14480. doi: 10.1039/d4dt01698j.
The impact of substituents at the 4- and 7-positions of 1,10-phenanthroline-2,9-dicarboxamides on the photophysical properties of the ligands and their coordination compounds with the lanthanide triad-europium, gadolinium, and terbium-was analyzed. This study demonstrates how modification of the electronic nature of ligands through the incorporation of diverse functional groups affects the luminescence properties of their complexes. The introduction of various substituents leads to the appearance of intra-ligand or ligand-to-ligand charge transfer (CT) states. The highest luminescence efficiency was observed for LH·Eu(NO3)3 ( = 54.1% and = 9.6%), suggesting strong luminescence quenching of the CT state. It was found that a relatively low Δ (∼3000 cm) supports direct energy transfer from S to T bypassing the CT state, even though it is outside Reinhoudt's optimal range. The introduction of fluorines leads to the strongest luminescence quenching among all the substituents.
分析了1,10 - 菲咯啉 - 2,9 - 二羧酰胺4位和7位取代基对配体及其与镧系元素三联体（铕、钆和铽）配位化合物光物理性质的影响。本研究表明，通过引入不同官能团来改变配体的电子性质如何影响其配合物的发光性质。各种取代基的引入导致配体内或配体间电荷转移（CT）态的出现。观察到LH·Eu(NO3)3的发光效率最高（Φ = 54.1%，τ = 9.6%），表明CT态存在强烈的发光猝灭。研究发现，相对较低的Δ（~3000 cm）支持从S到T的直接能量转移，绕过CT态，尽管它超出了Reinhoudt的最佳范围。在所有取代基中，氟的引入导致最强的发光猝灭。
