Low-Bias Conductance Mechanism of Diarylethene Isomers:a First-Principle Study  

异构二芳基乙烯分子结低偏压电导机制的第一性原理研究

作　　者：Ming-lang Wang Guang-ping Zhang Xiao-xiao Fu Chuan-kui Wang 王明郎;张广平;傅潇潇;王传奎(山东师范大学物理与电子科学学院,济南250358)

机构地区：[1]School of Physics and Electronics,Shandong Normal University,Jinan 250358,China

出　　处：《Chinese Journal of Chemical Physics》2020年第6期697-702,I0002,共7页化学物理学报（英文）

基　　金：supported by the National Natural Science Foundation of China(No.11874242 and No.21933002);the Natural Science Foundation of Shandong Province,China(No.ZR2019PA022).

摘　　要：The structure-property relationship of diarylethene(DAE)-derivative molecular isomers,which involve ring-closed and ring-open forms,is investigated by employing the nonequilibrium Green’s function formalism combined with density functional theory.Molecular junctions are formed by the isomers connecting to Au(111)electrodes through flanked pyridine groups.The difference in electronic structures caused by different geometry structures for the two isomers,particularly the interatomic alternative single bond and double bond of the ring-closed molecule,contributes to the vastly different low-bias conductance values.The lowest unoccupied molecular orbital(LUMO)of the isomers is the main channel for electron transport.In addition,more electrons transferred to the ring-closed molecular junction in the equilibrium condition,thereby decreasing the LUMO energy to near the Fermi energy,which may contribute to a larger conductance value at the Fermi level.Our findings are helpful for understanding the mechanism of low-bias conductance and are conducive to the design of high-performance molecular switching based on diarylethene or diarylethene-derivative molecules.

关 键 词：Molecular electronics Molecular switching Density functional theory Nonequilibrium Green’s function 

分 类 号：O625.12[理学—有机化学]