Frontier orbitals and quasiparticle energy levels in ionic liquids  

作　　者：Juhan Matthias Kahk Ivar Kuusik Vambola Kisand Kevin R.J.Lovelock Johannes Lischner 

机构地区：[1]Department of Materials,Imperial College London,South Kensington,London SW72AZ,UK [2]Institute of Physics,University of Tartu,W.Ostwaldi 1,50411 Tartu,Estonia [3]School of Chemistry,Food and Pharmacy,University of Reading,Reading RG66DX,UK [4]Department of Physics and Department of Materials and the Thomas Young Centre for Theory and Simulation of Materials,Imperial College London,London SW72AZ,UK

出　　处：《npj Computational Materials》2020年第1期441-447,共7页计算材料学（英文）

基　　金：J.M.K.and J.L.acknowledge support from EPRSC under Grant No.EP/R002010/1 and from a Royal Society University Research Fellowship(URF\R\191004);Via J.L.’s membership of the UK’s HEC Materials Chemistry Consortium,which is funded by EPSRC(EP/L000202);I.K.and V.K.acknowledge Estonian Centre of Excellence in Research project“Advanced materials and high-technology devices for sustainable energetics,sensorics and nanoelectronics”TK141(2014-2020.4.01.15-0011);K.R.J.L.acknowledges support from a Royal Society University Research Fellowship(URF\R\150353).

摘　　要：Ionic liquids play an important role in many technological applications and a detailed understanding of their frontier molecular orbitals is required to optimize interfacial barriers,reactivity and stability with respect to electron injection and removal.In this work,we calculate quasiparticle energy levels of ionic liquids using first-principles many-body perturbation theory within the GW approximation and compare our results to various mean-field approaches,including semilocal and hybrid density-functional theory and Hartree-Fock.We find that the mean-field results depend qualitatively and quantitatively on the treatment of exchange-correlation effects,while GW calculations produce results that are in excellent agreement with experimental photoelectron spectra of gas phase ion pairs and ionic liquids.These results establish the GW approach as a valuable tool for understanding the electronic structures of ionic liquids.

关 键 词：liquids IONIC QUASI 

分 类 号：O57[理学—粒子物理与原子核物理]