水二聚体分子间相互作用的理论研究

Theoretical Study on the Intermolecular Interaction of H_2O Dimers

作者利用从头算方法,在HF/6 31G 水平下得到了水二聚体势能面上的7种优化构型,并经MP2法、均衡法(CP)分别校正了电子相关和基组叠加误差(BSSE),通过对分子中的原子间的最短距离、分子间质心距离与各构型相互作用能的关系进行了分析、比较,得到了最稳定的构型,其对应的分子间相互作用能为:-21.0205kJ·mol-1.

Seven optimized geometry structures of H_2O dimers have been obtained using ab initio calculations at HF/6-31G^(**) level. All the binding energies of the dimers have evaluated as the sum of the HF interaction energies and MP2 correlation interaction energies, are corrected for the basis set superposition errors(BSSE). By comparing the relation between the distances of the two H_2O molecular mass center and the interaction energy with that between the shortest interatomtic distances of the dimer and the interaction energies, the most stable structure is achieved and the corresponding intermolecular interaction energy is-21.0205kJ/mol.