Long-range electron tunnelling in oligo-porphyrin molecular wires.
Nat Nanotechnol
; 6(8): 517-23, 2011 Jul 31.
Article
em En
| MEDLINE
| ID: mdl-21804555
ABSTRACT
Short chains of porphyrin molecules can mediate electron transport over distances as long as 5-10 nm with low attenuation. This means that porphyrin-based molecular wires could be useful in nanoelectronic and photovoltaic devices, but the mechanisms responsible for charge transport in single oligo-porphyrin wires have not yet been established. Here, based on electrical measurements of single-molecule junctions, we show that the conductance of the oligo-porphyrin wires has a strong dependence on temperature, and a weak dependence on the length of the wire. Although it is widely accepted that such behaviour is a signature of a thermally assisted incoherent (hopping) mechanism, density functional theory calculations and an accompanying analytical model strongly suggest that the observed temperature and length dependence is consistent with phase-coherent tunnelling through the whole molecular junction.
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Base de dados:
MEDLINE
Assunto principal:
Porfirinas
/
Nanotecnologia
/
Modelos Químicos
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article