Rectification and negative differential resistance via orbital level pinning.

ABSTRACT: A donor-acceptor system, 4-thiophenyl-azafulleroid (4TPA-C₆₀), is investigated at the point of HOMO/LUMO resonance and beyond to understand how negative differential resistance (NDR) features may be observed in such systems. Our previous investigation showed that charge transfer between the occupied and unoccupied states at resonance hindered crossing of the HOMO and LUMO levels, thus preventing the formation of an NDR feature. In this work, it is shown that the negative differential resistance feature of 4TPA-C₆₀ can be tailored based on the couplings at the metal/molecule interface. Ab initio calculations show that limited charge extraction from atomically sharp contacts results in a HOMO-LUMO pinning effect which delays the onset of the NDR feature. Subsequent unpi

SUBMITTER: Thong AZ 

PROVIDER: S-EPMC6002475 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature