Research Article

Nano Research

, Volume 3, Issue 5, pp 350-355

Open Access This content is freely available online to anyone, anywhere at any time.

Field effects on the statistical behavior of the molecular conductance in a single molecular junction in aqueous solution

  • Hui CaoAffiliated withDepartment of Theoretical Chemistry, School of Biotechnology, Royal Institute of TechnologySchool of Chemistry and Chemical Engineering, Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry of Ministry of Education, Nanjing University Email author 
  • , Jing MaAffiliated withSchool of Chemistry and Chemical Engineering, Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry of Ministry of Education, Nanjing University
  • , Yi LuoAffiliated withDepartment of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology

Abstract

We have combined molecular dynamics simulations with first-principles calculations to study electron transport in a single molecular junction of perylene tetracarboxylic diimide (PTCDI) in aqueous solution under external electric gate fields. It is found that the statistics of the molecular conductance are very sensitive to the strength of the electric field. The statistics of the molecular conductance are strongly associated with the thermal fluctuation of the water molecules around the PTCDI molecule. Our simulations reproduce the experimentally observed three orders of magnitude enhancement of the conductance, as well as the temperature dependent conductance, under the electrochemical gates. The effects of the molecular polarization and the dipole rearrangement of the aqueous solution are also discussed.
http://static-content.springer.com/image/art%3A10.1007%2Fs12274-010-1038-9/MediaObjects/12274_2010_1038_Fig1_HTML.jpg

Keywords

Molecular junction field effect solvent effect temperature effect statistical behavior