一价阳离子同甲醛的弱相互作用

Weak Interaction of One-value Ions and Formaldehyde

利用密度泛函理论方法,优化得出复合体系的稳定构型。由于氢离子的半径最小,与氧形成了典型的化学键结合。离解能的大小随离子半径的减小而增强,并产生电荷从羰基向离子上转移的现象,转移的电荷部分填充离子核外空轨道,引起电荷趋于均匀分布,从而降低整个体系的能量。分析了复合体系的振动频率,受离子的影响,羰基的振动强度总体变弱,不同离子对其影响程度不同。

The most stable configurations of the complexes were optimized by using density functional theory （DFT）. The typical chemical bond is formed between hydrogen ion and oxygen of formaldehyde due to the smaller hydrogen ionic radius. The values of the dissociation energies increase with the decrease of the ionic radii,and then the charge transfers from the carbonyl to the ions and partly occupies extranuclear orbital, causing the even distribution of the charge,which reduces the energies of the complexes. In addition, the vibration frequencies of the complexes were analyzed,showing they are affected obviously by the neighbouring ions, that the vibration strength of the carbonyl generally becomes weak and that different ions have different effects on the vibration frequencies.