Molecular dynamics simulations of temperature-dependent structures and dynamics of ethylammonium nitrate protic ionic liquid: The role of hydrogen bond

作者：Huang, Yiping; Zhou, Guobing; Li, Yunzhi; Yang, Zhen^*; Shi, Man; Wang, Xueping; Chen, Xiangshu^*; Zhang, Fei; Li, Wei

来源：Chemical Physics, 2016, 472: 105-111.

DOI：10.1016/j.chemphys.2016.03.020

• Protic ionic liquid
• Hydrogen bond
• Diffusion
• Ion-pair dissociation
• Molecular dynamics simulation

Molecular dynamics simulations have been employed to systematically investigate the structure and dynamics properties, hydrogen bond (HB) dynamics of protic ionic liquid (IL) ethylammonium nitrate (EAN) in the temperature range between 300 K and 400 K. The simulation results demonstrate clearly that the temperature almost has little influence on the structures of EAN IL, whereas the translational and the rotational motions of both cations and anions become much faster at higher temperatures. Furthermore, both anions and cations are found to display an obvious sub-diffusive behavior. These changes can be attributed to the temperature-dependent HB strength between the cations and the anions, where the strength of HBs decreases significantly with increasing temperature. Accordingly, the ion-pair association/dissociation dynamics decreases considerably with increasing temperature. Therefore, our simulations reveal at a molecular level that the HBs interactions play an essential role in determining the dynamics properties of protic ILs.

• 出版日期2016-6-15
• 单位南京大学; 江西师范大学