一例吡嗪基联吡啶镍配合物的合成、晶体结构及性质研究

Synthesis,Crystal Structure and Properties of a Pyrazinyl Bipyridine Nickel Complex

本文以多氮类化合物2,6-双(2-吡嗪基)-3,4′-联吡啶(dpyb)和Ni(NO_(3))_(3)·6H_(2)O为原料,采用溶剂热合成法得到了一例新的镍配合物[Ni(dpyb)_(2)](NO_(3))_(2)·(H_(2)O)_(3),通过X射线单晶衍射、红外和拉曼光谱对配合物的结构进行了表征。结果表明,此配合物为单核结构,单核单元通过分子间氢键的连接作用形成双核结构。通过Crystal Explorer 21程序对该配合物进行了Hirshfeld表面分析,结果表明配合物中存在较强的氢键作用。采用Gaussian 09W和Gauss View 5.0软件,运用B3LYP/6-311G(d,p)法计算了配体和配合物的前线分子轨道及能带间隙,计算结果证明此配合物具有较高的稳定性。此外还对自由配体及配合物[Ni(dpyb)_(2)](NO_(3))^(2)·(H_(2)O)_(3)的荧光性质进行了研究,研究结果发现,自由配体和金属Ni(Ⅱ)离子的配位,导致配合物的荧光强度减弱。

A new nickel complex[Ni(dpyb)2](NO3)2·(H2 O)3 was synthesized by means of solvent-thermal synthesis using 2,6-bis(2-pyrazinyl)-3,4′-bipyridine(dpyb),which is one of polynitrogen compounds,as the ligand and Ni(NO_(3))_(3)·6H_(2)O as raw materials.The structure of the complex[Ni(dpyb)2](NO_(3))_(2)·(H_(2)O)_(3)was characterized by X-ray single crystal diffraction,infrared spectroscopy and Raman spectroscopy.The results of structural analysis show that the complex was a mononuclear structure,and the mononuclear structure is further extended to the binuclear structure through intermolecular hydrogen bonds between the mononuclear units.The Hirshfeld surface analysis of the target complex was carried out using Crystal Explorer 21 software,and the results show that there is strong hydrogen bonding in the structure of[Ni(dpyb)2](NO_(3))_(2)·(H_(2)O)_(3).The frontline molecular orbitals and energy band gaps of the free ligand and the complex were also calculated by Gaussian 09W and Gauss View 5.0 software using the B3LYP/6-311G(d,p)method,and the results suggest that the complex has high chemical stability.The results of the computational study are in good agreement with the experiments.In addition,fluorescence analysis of the free ligand and complexe were performed,and the results indicate that compared with the free ligand,the fluorescence intensity of the complex is weakened,which is due to the coordination between the ligand and the Ni(Ⅱ)ion.