English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We examine theoretically the effects of the bonding geometries at thegold-thiol interfaces on the inelastic tunneling spectra of propanedithiolate(PDT) molecules bridging gold electrodes and show that inelastic tunnelingspectroscopy combined with theory can be used to determine these bondinggeometries experimentally. With the help of density functional theory, wecalculate the relaxed geometries and vibrational modes of extended moleculeseach consisting of one or two PDT molecules connecting two gold nanoclusters.We formulate a perturbative theory of inelastic tunneling through moleculesbridging metal contacts in terms of elastic transmission amplitudes, and usethis theory to calculate the inelastic tunneling spectra of the gold-PDT-goldextended molecules. We consider PDT molecules with both trans and gaucheconformations bound to the gold clusters at top, bridge and hollow bondingsites. Comparing our results with the experimental data of Hihath et al. [NanoLett. 8, 1673 (2008)], we identify the most frequently realized conformation inthe experiment as that of trans molecules top-site bonded to both electrodes.We find the switching from the 42 meV vibrational mode to the 46 meV modeobserved in the experiment to be due to the transition of trans molecules frommixed top-bridge to pure top-site bonding geometries. Our results also indicatethat gauche molecular conformations and hollow site bonding did not contributesignificantly to the experimental inelastic tunneling spectra. For pairs of PDTmolecules connecting the gold electrodes in parallel we find total elasticconductances close to twice those of single molecules bridging the contactswith similar bonding conformations and small splittings of the vibrational modeenergies for the modes that are the most sensitive to the molecule-electrodebonding geometries.

Identification of the Atomic Scale Structures of the Gold-Thiol Interfaces of Molecular Nanowires by Inelastic Tunneling Spectroscopy