Abstract

Two Cu/Zn complexes [Cu(4,4'-bipy)(H₂O)₂(ClO₄)₂]_nn(4,4'-bipy) (1) and [Zn(4,4'-bipy)(H₂O)₄]_3n6n(4,4'-bipy)6n(ClO₄)·2nH₂O (2) (4,4'-bipy = 4,4'-bipyridine) have been prepared via hydrothermal reactions and characterized by single-crystal X-ray diffraction. Both complexes feature an infinite 1-D chain-like structural motif with the metal ions surrounded by two nitrogen atoms and four oxygen atoms to yield a octahedral configuration. Both complexes have a 3-D coordination polymer network formed by the rich hydrogen-bonding interactions. Powder photoluminescence studies reveal that they have an emission in the blue (1) or red (2) region of the light spectrum. Time-dependent density functional theory investigation discover that the nature of the emission is resulted from the ligand-to-metal charge transfer for 1, as well as ligand-to-ligand charge transfer for 2. Narrow optical band gaps of 1.43 eV (1) and 2.24 eV (2) are found by the solid-state UV/vis diffuse reflectance spectra.

摘要

两个 Cu/Zn 配合物 [Cu(4,4'-bipy)(H ₂ O) ₂ (ClO ₄ ) ₂ ] _n n (4,4'-bipy) ( 1 ) 和 [Zn(4,4'-bipy )(H ₂ O) ₄ ] _{3 n} 6 n (4,4'-bipy)6 n (ClO ₄ )·2 n H ₂ O ( 2) (4,4'-bipy = 4,4'-bipyridine) 已通过水热反应制备并通过单晶 X 射线衍射进行表征。两种配合物都具有无限的一维链状结构基序，金属离子被两个氮原子和四个氧原子包围，形成八面体构型。两种配合物都具有由丰富的氢键相互作用形成的 3-D 配位聚合物网络。粉末光致发光研究表明它们在光谱的蓝色 ( 1 ) 或红色 ( 2 ) 区域发射。时间相关的密度泛函理论研究发现发射的性质是由 1 的配体-金属电荷转移以及 2的配体-配体电荷转移引起的. 固态 UV/vis 漫反射光谱发现1.43 eV ( 1 ) 和 2.24 eV ( 2 ) 的窄光学带隙。