Change search
ReferencesLink to record
Permanent link

Direct link
Bridge-Dependent Electron Transfer in Porphyrin-Based Donor-Bridge-Acceptor Systems
Umeå University, Faculty of Science and Technology, Chemistry.
Show others and affiliations
2001 (English)In: Journal of American Chemical Society, Vol. 123, no 13, 3069-80 p.Article in journal (Refereed) Published
Abstract [en]

Photoinduced electron transfer in donor-bridge-acceptor systems with zinc porphyrin (or its pyridine complex) as the donor and gold(III) porphyrin as the acceptor has been studied. The porphyrin moieties were covalently linked with geometrically similar bridging chromophores which vary only in electronic structure. Three of the bridges are fully conjugated -systems and in a fourth, the conjugation is broken. For systems with this bridge, the quenching rate of the singlet excited state of the donor was independent of solvent and corresponded to the rate of singlet energy transfer expected for a Förster mechanism. In contrast, systems with a -conjugated bridging chromophore show a solvent-dependent quenching rate that suggests electron transfer in the Marcus normal region. This is supported by picosecond transient absorption measurements, which showed formation of the zinc porphyrin radical cation only in systems with -conjugated bridging chromophores. On the basis of the Marcus and Rehm-Weller equations, an electronic coupling of 5-20 cm-1 between the donor and acceptor is estimated for these systems. The largest coupling is found for the systems with the smallest energy gap between the donor and bridge singlet excited states. This is in good agreement with the coupling calculated with quantum mechanical methods, as is the prediction of an almost zero coupling in the systems with a nonconjugated bridging chromophore.

Place, publisher, year, edition, pages
2001. Vol. 123, no 13, 3069-80 p.
URN: urn:nbn:se:umu:diva-8646DOI: doi:10.1021/ja003820kOAI: diva2:148317
Available from: 2008-02-05 Created: 2008-02-05 Last updated: 2011-01-13Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text
By organisation

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 28 hits
ReferencesLink to record
Permanent link

Direct link