CH_3(CH_2)_nSO_4^-(n=7～17)表面活性剂电子结构与表面张力的关系

Study on Characters of Electronic Structuresand Surface Tension for Anionic Surfactants CH_3(CH_2)_nSO_4^-(n=7～17) Using DFT Method

用B3LYP/6-31G*研究了不同烷基链阴离子表面活性剂的键长、键角和净电荷等随着碳原子数的增加而呈现的变化规律,考察了表面活性剂的结构与表面张力的关系。结果表明:(1)C-O键长和O-S-O平均键角与碳原子数有关;(2)端基净电荷和极性头净电荷随着碳原子增加而增加。

The geometries of the anionic surfactants with alkyl chain length were optimized using B3LYP/6-31G ＊ , respective- ly. The bond length, bond angle and net charges of the surface-active anions were obtained in gas. The relationships of struc- ture of surfactant and surface tension were studied. The calculation results showed that （1） C-O bond length and O-S-O bond angle are concerned with carbonyl atom number; （2）Qso4 and Qmax increased with carbonyl atom number increasing.