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Photoswitchable mixed valence.

Oliver S Wenger1

  • 1Georg-August-Universität Göttingen, Institut für Anorganische Chemie, Tammannstrasse 4, D-37077 Göttingen, Germany. oliver.wenger@chemie.uni-goettingen.de

Chemical Society Reviews
|March 10, 2012
PubMed
Summary
This summary is machine-generated.

Photoswitchable mixed valence systems offer controllable molecular conductivity. Light stimuli can significantly alter charge delocalization in these systems, paving the way for molecular electronics.

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Area of Science:

  • Molecular electronics
  • Supramolecular chemistry
  • Photochemistry

Background:

  • Molecular electronics requires controllable conductivity via external stimuli.
  • Photoswitchable mixed valence systems provide a platform for exploring conductivity control.
  • These systems feature photoisomerizable linkers connecting redox-active units.

Purpose of the Study:

  • To review photoswitchable mixed valence systems for molecular electronics.
  • To discuss the role of photoisomerizable units like dithienylethenes.
  • To explore the switching of charge delocalization using light stimuli.

Main Methods:

  • Utilizing cyclic voltammetry and optical absorption spectroscopy.
  • Comparing isomeric forms of photoswitchable systems.
  • Applying theoretical models to analyze charge delocalization.

Main Results:

  • Dithienylethenes and other units enable photoswitching.
  • Both metal-containing and organic redox units are employed.
  • Light stimulus can substantially increase charge delocalization.

Conclusions:

  • Photoswitchable mixed valence systems are key for molecular electronics.
  • These systems demonstrate tunable charge delocalization.
  • A light-induced change from class I to class II/III behavior is observed.