Conductance of alkanedithiol single-molecule junctions: a molecular dynamics study.
We study formation and conductance of alkanedithiol junctions using density functional based molecular dynamics. The formation involves straightening of the molecule, migration of thiol end-groups, and pulling out Au atoms. Plateaus are found in the low-bias conductance traces which decrease by 1 order of magnitude when gauche defects are present. We further show that the inelastic electron tunneling spectra depend on the junction geometry. In particular, our simulations suggest ways to identify gauche defects.
Paulsson
Magnus
M
School of Pure and Applied Natural Sciences, University of Kalmar, 391 82 Kalmar, Sweden. magnus.paulsson@hik.se
Krag
Casper
C
Frederiksen
Thomas
T
Brandbyge
Mads
M
D000473:Alkanes / Q000737:chemistry*; D003198:Computer Simulation; D003460:Crystallization / Q000379:methods; D004553:Electric Conductivity; D006046:Gold / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties
D000473:Alkanes; D046911:Macromolecular Substances; D013438:Sulfhydryl Compounds; D006046:Gold