Roles of Asymmetric Contacts and D-A substituent groups in Molecular Rectification:A First-Principles Study
Using density functional theory (DFT) combined with the first-principle nonequilibrium Greens function (NEGF),we investigate the electron-transport properties and rectifying behaviors of several molecular junctions based on the bis-2-(5-ethynylthienyl)ethyne (BETE) molecule.In order to examine the roles of different rectification factors,asymmetric electrode-molecule contacts and donor-acceptor substituent groups are introduced into the BETE-based molecular junction.The asymmetric current-voltage characteristics are obtained for the molecular junctions containing asymmetric contacts and donor-acceptor groups.In our models,the computed rectification ratios show that the mode of electrode-molecule contacts plays a crucial role for the rectification,and the rectifying effect is not enhanced significantly by introducing the additional donor-acceptor components for the molecular rectifier with asymmetric electrode-molecule contacts.The current-voltage characteristics and rectifying behaviors are discussed through transmission spectra,molecular projected self-consistent Hamiltonian (MPSH) states,and energy levels of MPSH states.The computational program packages in this work are Gaussian03 and ATK 2008.10.
Shundong Yuan Qunbo Mei Qidan Ling Lianhui Wang Wei Huang
Jiangsu Key Laboratory of Organic Electronics & Information Displays and Institute of Advanced Mater Jiangsu Key Laboratory of Organic Electronics & Information Displays and Institute of Advanced Mater Jiangsu Key Laboratory of Organic Electronics & Information Displays and Institute of Advanced Mater Jiangsu Key Laboratory of Organic Electronics & Information Displays and Institute of Advanced Mater
国际会议
南京
英文
424-447
2012-05-13（万方平台首次上网日期，不代表论文的发表时间）