Chaban Vitaly V, Fileti Eudes Eterno
Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo, 12247-014, São José dos Campos, SP, Brazil.
Phys Chem Chem Phys. 2015 Jun 28;17(24):15739-45. doi: 10.1039/c5cp00350d. Epub 2015 May 27.
Fullerenes are known to be polarizable due to their strained carbon-carbon bonds and high surface curvature. The electronic polarization of fullerenes is steadily of practical importance because it leads to non-additive interactions and, therefore, to unexpected phenomena. For the first time, hybrid density functional theory (HDFT) powered Born-Oppenheimer molecular dynamics (BOMD) simulations have been conducted to observe electronic polarization and charge transfer phenomena in the C60 fullerene at finite temperature (350 K). The non-additive phenomena are fostered by the three selected imidazolium-based room-temperature ionic liquids (RTILs). We conclude that although charge transfer appears nearly negligible in these systems, electronic polarization is indeed significant, leading to a systematically positive effective electrostatic charge on the C60 fullerene: +0.14e in [MMIM][Cl], +0.21e in [MMIM][NO3], and +0.17e in [MMIM][PF6]. These results are, to a certain extent, unexpected and provide a motivation for considering novel C60-RTILs systems. HDFT BOMD is a powerful tool for investigating electronic effects in RTIL and fullerene containing nuclear-electronic systems.
由于富勒烯中碳 - 碳键的张力和高表面曲率，它们具有可极化性。富勒烯的电子极化一直具有实际重要性，因为它会导致非加和相互作用，进而产生意想不到的现象。首次进行了基于杂化密度泛函理论（HDFT）的玻恩 - 奥本海默分子动力学（BOMD）模拟，以观察在有限温度（350K）下C60富勒烯中的电子极化和电荷转移现象。三种选定的基于咪唑鎓的室温离子液体（RTILs）促进了非加和现象。我们得出结论，尽管在这些系统中电荷转移似乎几乎可以忽略不计，但电子极化确实很显著，导致C60富勒烯上出现系统性的正有效静电荷：在[MMIM][Cl]中为 +0.14e，在[MMIM][NO3]中为 +0.21e，在[MMIM][PF6]中为 +0.17e。这些结果在一定程度上出乎意料，并为考虑新型C60 - RTILs系统提供了动力。HDFT BOMD是研究含离子液体和富勒烯的核 - 电子系统中电子效应的有力工具。
