Neglecting Polarizability in Polyethylene Oxide Accelerates Lithium Ion Transport
발표자
홍예성 (서강대학교)
연구책임자
성봉준 (서강대학교)
초록
내용
MD simulations are a powerful tool for investigating Li+ ion transport at the molecular scale, most studies neglect polarizability due to its high computational cost. However, we find that polarizability plays a critical role in accurately modeling Li+ ion transport. In this study, we perform all-atom MD simulations of LiPF6 in PEO system to see the effect of polarizability. We selectively activate and deactivate polarizability using the force field to observe the structural and dynamical changes in the PEO-Li+ system. The first peak of the Li-O RDF decreases in order PM > NP > IP, whereas the O-O RDF remains nearly unchanged regardless of polarizability. Additionally, the MSD of PEO does not change significantly with polarizability, while the MSD of Li+ ion shows considerable variation. These structural and dynamical observations show that polarizability increases the binding between Li+ ion and oxygen atoms in PEO chains, which slows down inter-chain hopping of Li+ ion.