Electron transport characteristics of the dimeric 1,4-benzenedithiol junction

Lin Wang; Shu-Ying Li; Jing-He Yuan; Jing-Ying Gu; Dong Wang; Li-Jun Wan

doi:10.1002/asia.201402196

Electron transport characteristics of the dimeric 1,4-benzenedithiol junction

Chem Asian J. 2014 Aug;9(8):2077-82. doi: 10.1002/asia.201402196. Epub 2014 Jun 6.

Authors

Lin Wang¹, Shu-Ying Li, Jing-He Yuan, Jing-Ying Gu, Dong Wang, Li-Jun Wan

Affiliation

¹ CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, the Chinese Academy of Sciences, Beijing, 100190 (People's Republic of China), Fax: (+86) 10-62558934; University of Chinese Academy of Sciences, Beijing, 100049 (People's Republic of China).

PMID: 24909757
DOI: 10.1002/asia.201402196

Abstract

Understanding the electron transport between single molecules connected through weak interaction is of great importance for molecular electronics. In this paper, we report measurements of the conductivity of the dimeric 1,4-benzenedithiol (BDT) junction using the scanning tunneling microscopy (STM)-based current-displacement I(s) method. The conductance was measured to be 6.14×10(-6) G0 , a value almost two orders of magnitude lower than that of the monomer BDT junction. In control experiments, the probability of junction formation decreased with the presence of tris(2-chloroethyl) phosphate (TCEP), a reducing reagent for the disulfide bond. According to theoretical computations, the dihedral angle of the SS bond tends to take a perpendicular conformation. This non-conjugated structure localizes the electron distribution and accounts for the low conductivity of the disulfide linkage.

Keywords: disulfide bond; electron transport; scanning tunneling microscopy; single-molecule studies.