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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present a quaternion-inspired formalism specifically developed to evaluatethe electric current that traverses a single molecule subjected to anexternally applied voltage. The molecule of interest is covalently connected totwo small metallic clusters, forming an extended molecule complex. Thequaternion approach allows for an integrated treatment of the charge transportin single molecules where both ballistic and co-tunneling (coherent) mechanismsare taken on equal footing, although only in the latter case the presence ofeventual transient charged states of the system needs to be considered. We usea Dyson series to obtain a generalized Fermi golden rule, from which we derivean expression for the net current the two electrodes: in doing this, we takeinto account all possible transitions between electronic states localized atthe electrodes and levels in the extended molecule complex. In fact, one canapply the method to the entire range of coupling regimes, not only in the weakor strong cases, but also in intermediate situations, where ballistic andco-tunneling processes compete with each other. We also discuss initial resultsof the application of this formalism to the description of the electronictransport in two small organic molecules representative of two different limitsituations. In the first case, a conjugated molecule (where spatiallydelocalized molecular orbitals favor ballistic contributions) is considered,and in the second, the current traverses a saturated hydrocarbon (whosestructure should contain more localized molecular orbitals). In both cases, wefully describe the field-induced self-adjustment of the electronic levels ofthe extended molecule complex at an ab initio quantum chemical level, usingdensity functional theory.

A Generalized Landauer Approach for Electron Transport in a Single Molecule