CaltechAUTHORS
  A Caltech Library Service

Picosecond Fluorescence Studies on Intramolecular Photochemical Electron Transfer in Porphyrins Linked to Quinones at Two Different Fixed Distances

Leland, B. A. and Joran, A. D. and Felker, P. M. and Hopfield, J. J. and Zewail, A. H. and Dervan, P. B. (1985) Picosecond Fluorescence Studies on Intramolecular Photochemical Electron Transfer in Porphyrins Linked to Quinones at Two Different Fixed Distances. Journal of Physical Chemistry, 89 (26). pp. 5571-5573. ISSN 0022-3654 . http://resolver.caltech.edu/CaltechAUTHORS:20160511-150856953

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20160511-150856953

Abstract

Fluorescence lifetimes were determined for porphyrins linked to quinones at two different fixed distances by bicyclo[2.2.2]octyl spacers. Electron-transfer rate constants for the one- and two-spacer homologues were calculated from the lifetimes. The incremental effect of the second spacer is to decrease the electron-transfer rate by at least a factor of 500-1600 depending on solvent. Lifetime measurements in solvents of different polarities indicate that the electron-transfer rate decreases with increasing solvent polarity. Experiments at low temperature (77 K) revealed fast nearly temperature-independent electron transfer characterized by nonexponential decays in the fluorescence profiles of the one-spacer compound, in contrast to essentially monoexponential decays at room temperature. Low temperatures appear to freeze out the rotational motion of the chromophores and the observed fluorescence decays may be explained as electron transfer from an ensemble of rotational conformations.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1021/j100272a002DOIArticle
http://pubs.acs.org/doi/abs/10.1021/j100272a002PublisherArticle
Additional Information:© 1985 American Chemical Society. (Received: September 24, 1985) We are grateful to the National Science Foundation (CHE-8305790 and DMR-8107494) for support of this research.
Funders:
Funding AgencyGrant Number
NSFCHE-8305790
NSFDMR-8107494
Record Number:CaltechAUTHORS:20160511-150856953
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20160511-150856953
Official Citation:Picosecond fluorescence studies on intramolecular photochemical electron transfer in porphyrins linked to quinones at two different fixed distances B. A. Leland, A. D. Joran, P. M. Felker, J. J. Hopfield, A. H. Zewail, and P. B. Dervan The Journal of Physical Chemistry 1985 89 (26), 5571-5573 DOI: 10.1021/j100272a002
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:67016
Collection:CaltechAUTHORS
Deposited By: Victoria Brennan
Deposited On:19 May 2016 23:57
Last Modified:19 May 2016 23:57

Repository Staff Only: item control page