Ab initio investigation of possible candidate structures and properties of water cluster (H2O)(7)(+) via particle swarm optimization method

作者：Li, Guo-Jun; Hu, Cui-E; Tang, Mei; Chen, Xiang-Rong^*; Cai, Ling-Cang

来源：Computational and Theoretical Chemistry, 2017, 1099: 123-132.

DOI：10.1016/j.comptc.2016.11.028

• (H2O)(7)(+) cluster
• Gibbs free energy
• Singly occupied molecule orbital (SOMO)
• Vibrational analysis
• Topological analysis

The structures of the ionized water cluster (H2O)(7)(+) are investigated through the particle swarm optimization method combined with ab initio method. Some new lower energy structures are found after geometric optimization at the MP2/aug-cc-pVDZ level when compared with previous report. We studied the effect of the zero point vibrational energies on the relative energy order of these isomers, the relationship between their schemes and their relative energies, and the composition of their foremost molecular orbitals. The relative free energies of (H2O)(7)(+) isomers below 350 K, the infrared spectra of five lowest energy isomers, and their electronic characteristics were discussed in detail, respectively. Based on topological analysis and reduced density gradient analysis, we find that the interaction between H3O+ core and water molecules is stronger than the interaction between OH radical and water molecules by comparing the structural and the bonding strengths within these cationic water clusters.

• 出版日期2017-1-1
• 单位重庆师范大学; 中国工程物理研究院流体物理研究所; 四川大学; 中国工程物理研究院