几种新型双吡唑衍生物缓蚀性能的理论研究

Theoretical study of some new bipyrazole derivatives and their potential activity as corrosion inhibitors

通过量子化学计算中的密度泛函理论(DFT)/B3LYP方法在6-311+G(d,p)水平上对3种新型双毗唑衍生物5,5'-二甲基-4-乙酯基-1'氢-1,3'-二吡唑(Bipl)、1,1',5,5'一四甲基-1氢,1'氢-3,3'-二吡唑(Bip2)和3-(溴甲基)-5,5'-二甲基-1'氢-1,3'-二吡唑(Bip3)的缓释性能与结构关系进行了研究。用Fukui指数分析了分子中反应活性位点。结果表明全局活性参数最高占据轨道能量(E_(HOMO))、偶极矩(μ)、电负性(X)及电子转移数(△N)与缓释性能有良好的关系。缓蚀性能的理论评价结论与实验结果相吻合。

A theoretical study of three new bipyrazole derivatives, ethyl 5,5＇-dimethyl-1＇H-1, 3＇-bipyrazole-4-carboxylate （Bipl）, 1,1＇,5,5＇-tetramethyl-1H, 1＇H-3,3＇-bipyrazole （Bip2）, and 3-（bromomethyl）-5,5＇-dimethyl-1＇H-1,3＇-bipyrazole （Bip3） was performed using density functional theory （DFT） at the B3LYP/6-311G＋（d,p） level in order to elucidate the different inhibition efficiencies and reactive sites of these compounds as corrosion inhibitors. In addition, the local reactivity was analyzed through the Fukui function. The results showed that the global chemical reactivity parameters, such as EuoMo, dipole moment （μ ）, electronegativity（ X ）, global hardness （ η ） and the fraction of electrons transferred from the inhibitor molecule to the metallic atom （△N） had a good relation with the inhibition efficiencies. The calculated results are in agreement with the experimental data on the whole.