On the interface dipole at the pentacene-fullerene heterojunction: A theoretical study
2010 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 114, no 7, 3215-3224 p.Article in journal (Refereed) Published
The electronic structure at organic/organic interfaces plays a key role, among others, in defining the quantum efficiency of organics-based photovoltaic cells. Here, we perform quantum-chemical and microelectrostatic calculations on molecular aggregates of various sizes and shapes to characterize the interfacial dipole moment at pentacene/C60 heterojunctions. The results show that the interfacial dipole mostly originates in polarization effects due to the asymmetry in the multipolar expansion of the electronic density distribution between the interacting molecules, rather than in a charge transfer from donor to acceptor. The local dipole is found to fluctuate in sign and magnitude over the interface and appears as a sensitive probe of the relative arrangements of the pentacene and C60 molecules (and of the resulting local electrical fields sensed by the molecular units).
Place, publisher, year, edition, pages
2010. Vol. 114, no 7, 3215-3224 p.
Electrical field, Electronic density distribution, Interacting molecules, Interface dipole, Interfacial dipoles, Molecular aggregate, Molecular units, Multipolar expansion, Organics, Pentacenes, Polarization effect, Sensitive probe, Theoretical study
IdentifiersURN: urn:nbn:se:kth:diva-149424DOI: 10.1021/jp910005gISI: 000274578700054ScopusID: 2-s2.0-77649129684OAI: oai:DiVA.org:kth-149424DiVA: diva2:739395
FunderEU, FP7, Seventh Framework Programme, FP7-NMP-228424
QC 201408212014-08-212014-08-212014-08-21Bibliographically approved