以1-(2-甲基-苯并咪唑基)-1,4,7-三氮杂环癸烷为配体的铜(Ⅱ)配合物的晶体结构和理论计算（英文）

Crystal Structures and Theoretical Calculation of Copper(Ⅱ) Complex Based on Tetradentate Ligand 1-(benzimidazolyl-2-methyl)-1,4,7-Triazacyclodecane

以1,4,7-三氮杂环癸烷和氯甲基苯并咪唑为起始原料,一步反应合成了一种新的N-功能化的四齿配体,并用X射线衍射法测定了其铜(Ⅱ)配合物([CuC lL]·[ClO 4])的晶体结构。结果表明,该配合物由阳离子单元[CuC lL]+和阴离子单元ClO-4组成,中心铜原子与一个氯离子、大环配体的三个氮原子和苯并咪唑基的一个氮原子配位,形成扭曲的四方锥结构。为了揭示配合物的配位性质与电子结构之间的关系,基于密度泛函理论,利用DFT-B3LYP/6-31G(d)研究了配合物的前沿分子轨道分布(HOMO,LUMO),Mulliken原子电荷和能带。计算结果表明,2-甲基苯并咪唑基侧基的N(4)原子比N(5)原子具有更强的电荷转移能力,因为N(4)的HOMO和LUMO组分比N(5)的大,证明了Cu和N(4)之间形成了配位键。此外,配合物的前线分子轨道能分别为-0. 18722 a. u.(HOMO)和-0. 10239 a. u.(LUMO)。配合物的能级差ΔE(ELUMO-EHOMO)值为0. 08483 a. u.,较小,说明其在光照条件下容易激发,不稳定。

One new N-functionalized tetradentate ligand was synthesized by one-step reaction using 1,4,7-triazacyclodecane and chloromethyl benzimidazole as starting materials without using the reagent to protect,and its copper(II)complex([CuClL]·[ClO 4])was determined by X-ray diffraction.The crystal structure showed that complex is composed of a cationic units[CuClL]+and an anion unit ClO-4,the center copper atoms is five-coordinate,containing a chloride ion,three nitrogen atoms of macrocyclic ligands and one nitrogen atom of benzimidazolyl,forming a distorted square pyramid.In order to discover the relationship between the coordination property of complex and electronic structures,the frontier molecular orbital profiles(HOMO,LUMO),Mulliken atomic charges and bandgaps of the complex had been studied by means of DFT-B3LYP/6-31G(d)in Gaussian 03 based on the density functional theory.The results of calculation show that the N(4)atom of benzimidazolyl-2-methyl pendant groups possesses more stronger charge transfer ability than that of N(5)atom because the HOMO and LUMO components of N(4)are larger than that of N(5)according to the frontier molecular orbital profiles,and proved the coordination bonds was formed between Cu and N(4).In addition,the frontier molecular orbital energy of complex is-0.18722 a.u.(HOMO)and-0.10239 a.u.(LUMO).TheΔE(ELUMO-EHOMO)value of complex is 0.08483 a.u.,which is smaller and proves that it can be excitated easily in the illumination.