咪唑啉衍生物与Fe_4簇模型相互作用的密度泛函理论研究  

Density Functional Theory Study of Interaction between Imidazoline Derivatives and Fe_4 Cluster Model

作　　者：陈润荃 莫桂娣[1] 曾兴业[1] 周如金[1] 梁朝林[1] 

机构地区：[1]广东石油化工学院化学工程学院,茂名525000

出　　处：《腐蚀与防护》2015年第2期132-136,143,共6页Corrosion & Protection

基　　金：国家自然科学基金(21176050)

摘　　要：采用量子化学计算方法的密度泛函理论(DFT),在BPW91/6-311G(d,p)基组水平上优化了四个咪唑啉类衍生物和Fe4簇模型的基态结构。在此基础上,用相同的基组水平和极化连续介质模型(PCM)分别计算了四个分子在气相,水相和双电层中的前线轨道能量,以及与Fe4簇模型的结合位点和结合能。结果表明,咪唑啉类衍生物的负电荷主要分布在咪唑啉环的氮原子和侧链的氧(或硫)原子上;在溶剂中,其缓蚀率与HOMO轨道能量呈正相关,四个化合物均可向Fe4簇原子转移电荷。吸附位点和结合能分析表明咪唑啉环上的氮原子和侧链的氧(或硫)原子可与铁原子以化学吸附的方式结合,形成稳定的吸附络合物,在侧链上的结合能比与环上结合能相对更高。The geometry and electronic structural features of four kinds of imidazoline derivatives were studied using density functional theory（DFT）of quantum chemistry calculation method,based on BPW91/6-311G（d,p）basis set level.Based on their geometric structures,the frontier orbital energies,adsorption sites and binding energies of interaction between these four compounds and Fe4 cluster model were calculated using the same basis set and employing the polarizable continuum medium model（PCM）in the gas phase,aqueous phase and electric double layer,respectively.The results indicated that the negatived charge of imidazoline derivatives were mainly distributed on N atoms in imidazoline ring and O（or S）atoms in side chain.In solvent,the inhibition efficiency was positively correlated with the HOMO orbital energy,and imidazoline derivatives were easy to transfer charges toward Fe atom.Adsorption sites and binding energy analyses suggest that the N atoms of imidazoline ring and the O（or S）atoms on side chain can bond with Fe atom as chemical adsorption.The binding energy of side chain is relatively larger than that of the ring.

关 键 词：咪唑啉衍生物 Fe4簇模型 吸附位点 密度泛函理论 

分 类 号：TG174.42[金属学及工艺—金属表面处理]