中文摘要：

利用密度泛函理论（DFT），在B3LYP／6—31G水平下对十二伯胺、十四伯胺、十六伯胺和十八伯胺的阳离子分子构型进行优化，得到了4种胺阳离子的红外光谱频率，净电荷分布，偶极矩及前线轨道能量和组成．探讨了伯胺阳离子分子结构与氧化锌浮选性能的关系．研究结果表明胺阳离子碳链长度从十二增加到十八时，其偶极矩和最高占据轨道（HOMO）能量均随碳原子数增加而增大，而最低空轨道（LUMO）能量则基本不变．伯胺阳离子碳链长度对氧化锌捕收性能的影响，主要取决于胺的偶极子和矿物之间的定向作用力．△EHOMO-LUMO可以作为伯胺捕收性活性的判据．

英文摘要：

The cationic structures of dodecylamine, tetradecylamine, hexadecylamine and octadecylamine have been optimized.using DFT method at the B3LYP/6 - 31G level. The infrared spectrum frequency, distribution of Mulliken charge, dipole moment, frontier molecular orbital energy and its compose have been calculated. The relationship between cationic structure of amine and the flotation performance of zinc oxide has been discussed. The results show that the dipole moment and HOMO energy increase when the number of carbon atoms increases from 12 to 18, while the LUMO energy keeps unchanged. The collecting ability of primary amine cation with different carbon atoms for zinc flotation depends on the orientation interaction force between dipoles of amine cation and the minerals.△EHOMO- LUMOcan be considered as the judgment of the reactivity of collecting ability of primary amine cation.