A switchable self-assembling and disassembling chiral system based on a porphyrin-substituted phenylalanine–phenylalanine motif

DOI: 10.1038/ncomms12657

Authors: Georgios Charalambidis (University of Crete) , Evangelos Georgilis (University of Crete) , Manas K. Panda (University of Crete) , Christopher E. Anson (Karlsruhe Institute of Technology (KIT)) , Annie K. Powell (Karlsruhe Institute of Technology (KIT)) , Stephen Doyle (Karlsruhe Institute of Technology) , David Moss (Karlsruhe Institute of Technology) , Tobias Jochum (Karlsruhe Institute of Technology) , Peter N. Horton (University of Southampton) , Simon J. Coles (University of Southampton) , Mathieu Linares (Linköping University) , David Beljonne (Université de Mons—UMONS) , Jean-Valère Naubron (Aix Marseille Université) , Jonas Conradt (Karlsruhe Institute of Technology) , Heinz Kalt (Karlsruhe Institute of Technology) , Anna Mitraki (University of Crete; Institute of Electronic Structure and Laser (I.E.S.L.) Foundation for Research and Technology Hellas (FO.R.T.H.)) , Athanassios G. Coutsolelos (University of Crete) , Teodor Silviu Balaban (Aix Marseille Univ, CNRS)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Communications , VOL 7

State: Published (Approved)
Published: September 2016
Diamond Proposal Number(s): 8521

Abstract: Artificial light-harvesting systems have until now not been able to self-assemble into structures with a large photon capture cross-section that upon a stimulus reversibly can switch into an inactive state. Here we describe a simple and robust FLFL-dipeptide construct to which a meso-tetraphenylporphyrin has been appended and which self-assembles to fibrils, platelets or nanospheres depending on the solvent composition. The fibrils, functioning as quenched antennas, give intense excitonic couplets in the electronic circular dichroism spectra which are mirror imaged if the unnatural FDFD-analogue is used. By slightly increasing the solvent polarity, these light-harvesting fibres disassemble to spherical structures with silent electronic circular dichroism spectra but which fluoresce. Upon further dilution with the nonpolar solvent, the intense Cotton effects are recovered, thus proving a reversible switching. A single crystal X-ray structure shows a head-to-head arrangement of porphyrins that explains both their excitonic coupling and quenched fluorescence.

Journal Keywords: Self-assembly; Structure elucidation

Diamond Keywords: Artificial Photosynthesis; Bacteria

Subject Areas: Chemistry, Biology and Bio-materials, Energy


Instruments: I19-Small Molecule Single Crystal Diffraction

Added On: 18/11/2016 14:37

Documents:
ncomms12657.pdf

Discipline Tags:

Earth Sciences & Environment Sustainable Energy Systems Energy Climate Change Physical Chemistry Chemistry Engineering & Technology

Technical Tags:

Diffraction Single Crystal X-ray Diffraction (SXRD)