咪唑啉缓蚀剂构效关系的量子化学研究

Quantum chemistry study on the structure-activity relationship of imidazoline inhibitors

运用Gaussian 03W程序,采用密度泛函理论(DFT)的B3LYP/6-311++G方法对26种咪唑啉缓蚀剂进行结构优化,获得它们的稳定构型和量化参数。通过相关性分析,从9种量化参数中选出4种影响缓蚀剂缓蚀效率的活性参数,然后利用多元线性逐步回归分析方法,研究这4种参数和咪唑啉缓蚀剂缓蚀效率η的关系,建立QSAR方程。结果表明,该类缓蚀剂的最低未占据轨道能量(ELUMO),咪唑环上非氢原子净电荷之和(Qring),分子偶极矩(μ)以及分子总能量(ET)对缓蚀效率影响最大,其结果可为新型咪唑啉缓蚀剂的设计提供参考。

The optimized structures and the quantum chemical parameters of 26 kinds of imidazoline inhibitors have been obtained by using Gaussion03W package of programs at B3LYP/6-311＋＋G level. Via correlation analysis, 4 main independent factors affecting the activity of the compounds were selected out from 9 chemical parameters. The relationship between the 4 chemical parameters and correlation rate was studied, and QSAR equations were formulated by using a stepwise multiple linear regression method. The results indicated that, the energy of low unoccupied molecular orbital（LUMO）, the net charges of the imidazole ring（Qring）, mulecual dipole moment of（μ）and the total energy of the molecule（E_T）have the most significant contributions to the corrosion rate. Moreover, the results provided a theoretical foundation for new corrosion inhibitors.