Ultrafast energy transfer within cyclic self-assembled chlorophyll tetramers

  • Posted on: 10 July 2014
  • By: admin
TitleUltrafast energy transfer within cyclic self-assembled chlorophyll tetramers
Publication TypeJournal Article
Year of Publication2007
AuthorsKelley R.F, Goldsmith R.H, Wasielewski M.R
JournalJournal of the American Chemical Society
Date PublishedMay 23
ISBN Number0002-7863
Accession NumberISI:000246535300020
Keywordsbiological macromolecules, scattering, spectroscopic properties, structural-characterization, template-directed synthesis

We have prepared a zinc chlorophyll (ZC) derivative that self-assembles into a cyclic tetramer as evidenced by small-angle X-ray scattering studies in solution using a synchrotron source. This cyclic tetramer exhibits intramolecular energy transfer rates determined from singlet-singlet annihilation and transient absorption anisotropy studies that are comparable to those observed previously only for covalent ring structures. The larger transition dipole moment for the lowest energy electronic transition of ZC compared to that of metalloporphyrins increases the rate of Forster (through-space) energy transfer between the chlorophylls. Our synthetic and self-assembly strategy makes it possible to design larger monodisperse chlorophyll rings for energy transfer in artificial photosynthetic systems.

Alternate JournalJ Am Chem Soc