Acta Phys. -Chim. Sin. ›› 2008, Vol. 24 ›› Issue (08): 1445-1450.doi: 10.3866/PKU.WHXB20080820

• ARTICLE • Previous Articles     Next Articles

Electron Transport Properties of DiphenylacetyleneMolecular Wire

LI Yan-Wei; YAO Jin-Huan; YANG Chuan-Lu   

  1. Key Laboratory of New Processing Technology for Nonferrous Metals and Materials of the Ministry of Education, Guilin University of Technology, Guilin 541004, Guangxi Zhuang Autonomous Region, P. R. China; Department of Material and Chemical Engineering, Guilin University of Technology, Guilin 541004, Guangxi Zhuang Autonomous Region, P. R. China; College of Physics and Electronic Engineering, Ludong University, Yantai 264025, Shandong Province, P. R. China
  • Received:2008-02-13 Revised:2008-04-29 Published:2008-08-06
  • Contact: LI Yan-Wei E-mail:lywhit@126.com

Abstract: The electron transport properties of diphenylacetylene molecular wires with various conformations were studied by the first-principles density functional theory (DFT) and the non-equilibriumGreen function (NEGF) technique. The electron transport properties were discussed in terms of the spatial distributions of molecular orbitals and the transmission spectra of the molecular wires under various applied voltages. The results demonstrated that with the increase of molecular torsion, the LUMO-HOMO gap increased and transmission spectrum decreased. Under the influence of applied voltage, the HOMO and LUMO tended to move to low and high potential sides of the molecule, respectively. Current -voltage calculations revealed that the planar molecule was the most conductive. With the increasing torsional angle, the molecular conductance decreased and the perpendicular molecule conductance was the worst. Quantitative relationship between molecular torsion and molecular conductance was given.

Key words: Molecular wire, Diphenylacetylene, Molecular conformation, Electron transport

MSC2000: 

  • O641