A tridentate bisbenzimidazole‐pyridine ligand (L‐C⁵) with two pentyl side‐units and its metal complexes with Mn²⁺, Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺ and Zn²⁺ metal ions were synthesized and characterized. The structures of the ligand (L‐C⁵) and its five coordinate [Mn(L‐C⁵)Cl₂] were elucidated by single crystal X‐ray diffraction studies. The absorption and photoluminescence properties of the compounds were studied in solution media. The ligand is highly fluorescent, and binding of the metal ions to the ligand has caused significant changes in the emission band (shift or quenching). Moreover, the effect of aggregation on UV–Vis. absorption and emission properties was examined in MeOH‐water mixtures. The ligand was found to show aggregation‐induced quenching in the MeOH‐water mixture. The ligand was also screened for its colorimetric and fluorometric sensing ability of several metal ions [Na⁺, K⁺, Mg²⁺, Al³⁺, Ca²⁺, Mn²⁺, Fe²⁺, Fe³⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Hg²⁺, Pb²⁺]. The ligand showed selective sensing ability towards Zn²⁺, and the limit of detection was calculated as 3.09 × 10⁻⁷ m. The ligand also showed a distinguishable color change in the presence of Fe²⁺ under daylight.

中文翻译：

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三齿苯并咪唑配体及其金属配合物：合成，表征，光物理和传感器性能

合成了具有两个戊基侧单元的三齿双苯并咪唑吡啶配体（LC- ⁵）及其与Mn 2 ⁺，Fe 2 ⁺，Co 2 ⁺，Ni 2 ⁺，Cu ²⁺和Zn ²⁺金属离子的金属配合物和特点。配体（L–C ⁵）及其五个配位[Mn（L–C ⁵）Cl _2的结构通过单晶X射线衍射研究阐明了]。在溶液介质中研究了化合物的吸收和光致发光性质。配体具有很高的荧光性，金属离子与配体的结合已导致发射带发生明显变化（移动或猝灭）。此外，聚集对UV-Vis的影响。在MeOH-水混合物中检查了吸收和发射特性。发现该配体在MeOH /水混合物中显示出聚集诱导的猝灭。还对配体的几种金属离子[Na ⁺，K ⁺，Mg 2 ⁺，Al ³⁺，Ca 2 ⁺，Mn 2 ⁺，Fe 2 ⁺，Fe³⁺，Co 2 ⁺，Ni 2 ⁺，Cu 2 ⁺，Zn 2 ⁺，Hg 2 ⁺，Pb ²⁺ ]。该配体表现出对Zn ^2+的选择性感测能力，计算的检出限为3.09×10 ^-7 m。在白天，在Fe ²⁺存在下，配体也显示出明显的颜色变化。