羟基二酰亚胺二聚体分子间相互作用的量子化学研究

Quantum Chemical Study on Intermolecular Interaction for Dimers of Hydroxydiimide

采用从头算MP2方法在 6 311++G 基组水平上讨论了CP梯度校正对两种羟基二酰亚胺异构体所组成的二聚体的相互作用能和几何结构的影响 ,并利用分子中的原子理论 (Atomsinmolecules ,AIM)计算了五个拓扑参数 :键临界点的电荷密度、电荷密度的Laplacian值、氢键中氢原子的体积、氢原子集居数、氢原子能量来表征氢键的形成 .最后在所研究的多种构型氢键体系中还讨论了二聚体的相互作用能与氢键临界点的电荷密度、质子供体X—H键长的线性相关性问题 .结果表明这种线性相关性的存在有范围限制 。

MP2/6-311 + + G* * were applied to discussing the effects of the counterpoise-corrected gradient procedure on the interaction energies and the geometries of dimers constituted by the two isomers of hydroxydiimide. Hydrogen bonds (HB) could,be characterized by five topological, parameters: charge density in HB, its Laplacian, atomic populations and atomic volumes as well as atomic energies of hydrogen atom in HB evaluated by AIM (atoms in molecules). Linear correlations of the interaction energies of the dimmers with the charge densities in the HBs and with the proton donor X-H bond lengths were discussed in various conformations of the HB systems studied here. The results indicated that the linear correlation was limited and would be affected by the conformations of the complexes and the constituting monomers.