A Theoretical Investigation of Ionic Liquids Formed between Protonated Betaine Cation and Bis(trifluoromethylsulfonyl)imide Anion

作者：Wu Yang^*; Fan Cui'e; Zhang Lina; Kong Yuxia

来源：Acta Chimica Sinica, 2011, 69(22): 2682-2690.

• ionic liquids
• [Hbet][Tf(2)N]
• H-bonds
• natural population analysis (NPA)
• NBO
• atoms in molecules (AIM)

The interaction mechanisms between protonated betaine cation ([Hbet](+)) and bis(trifluoromethylsulfonyl)imide anion ([Tf(2)N](-)) were investigated at the B3LYP/6-311+G(d,p) level, and six stable isomers of [Hbet][Tf(2)N] were optimized. The optimized structures, energies and natural population analysis (NPA) were presented and analyzed in terms of their possible correlation with the interaction energies and the H-bond separations. Theoretical results indicate that the [Hbet](+) and [Tf(2)N](-) can form considerably strong H-bond interactions, which is mainly attributed to the interaction between the lone pairs of O, N atoms in [Tf(2)N](-) and the antibonding orbital of O-H, C-H in [Hbet](+) Atoms in molecules (AIM) analyses indicate that the H-bond between [Hbet](+) and [Tf(2)N](-) is primarily ionic character. The preliminary analysis of cation-anion interactions provides some initial hints as to the structural factors contributed to melting point and selective extraction of metal ions.

• 出版日期2011-11-28
• 单位辽宁大学