用量子化学密度泛函理论研究环状含氮化合物分子结构与缓蚀性能的关系

用量子化学计算泛函密度理论(DFT)中的B3LYP方法，在6-31G基组水平上，对5种环状含氮化合物：3-氨基-1,2，4-三唑、2-氨基-1，3，4-二氢噻唑、5-对甲苯基-1，3，4-三唑、3-氨基-5-甲硫基-1，2，4-三唑和2-氨基苯咪唑的缓蚀性能与分子结构及电子结构的关系进行了研究，用Fukui指效分析了分子中原子的反应性．结果表明文中涉及到的分子均为存在共轭体系的平面分子，缓蚀效率与分子的最高占据轨道的能量EHOMO、最低空轨道与最高占据轨道的能量差△E(ELUMO-EHOMO)有较好的相关性．可以认为缓蚀剂分子在金属表面通过亲核作用与金属作用而形成吸附膜。该类缓蚀剂分子是通过吡啶氮原子提供电子与金属发生作用的．

THE MOLECULAR STRUCTURE AND CORROSION INHIBITOR EFFICIENCY OF SOME CYCLIC NITROGEN COMPOUNDS:AN DFT STUDY

The relationship between corrosion inhibitor efficiency of some cyclic nitrogen compounds and their electronic properties of molecules has been carried out by using the quantum chemistry calculation, at the level of B3LYP with the 6-31G base sets.The chosen 5 compounds are:3-amino-1,2,4-triazole(3-ATA),2-amino-1,3,4-thiadiazole(2-ATDA),5-(p-tolyl)-1,3,4-triazole(TTA),3-amino-5-methylmercapto-1,2,4-triazole (3-AMTA) and 2-aminobenzimidazole.The reactivity was analyzed in terms of the Fukui indices.It is found that the molecules involved in this study are planar structure with conjugate system and the corrosion inhibition efficiencies have a certain linearity relation to energy of HOMO,the energy gap between LUMO and HOMO.It may be considered that these compounds are absorbed on the metal surface because the nitrogen atoms,which belong to pyridine type,offer electron pairs to the unoccupied atomic orbital.