Prof. Stéphane Rigaut

 [Carbon-Rich Systems and Molecular  Electronics]

 UMR 6226 "Sciences Chimiques de Rennes"
 Université Rennes I. Campus de Beaulieu.
 263 av. du Général Leclerc.
 35042 Rennes Cedex. France
 Building 10C, Room 003
 Telephone : 33 (0) 2 23 23 57 67 
 Fax : 33 (0) 2 23 23 69 39

Ph.D students

Emmanuel DI PIAZZA, since 2007

Yves-Marie HERVAULT since 2009

Research interests

Metal complexes which display ligand-mediated electronic effects including electron-transfer phenomena have attracted increasing interest. Indeed, the understanding and control of electron transfer reactions over nanometric distances constitute major challenges in science as it is a fundamental process to numerous complex chemical systems ranging from life processes to electronic devices.

We are interested in the study of electron transfer processes / electronic communication between redox centres using the fragment [RuCl(dppe)2]+ (dppe = 1,2-bis(diphenylphosphino)ethane) in new carbon-rich polymetallic complexes with unusual topologies.

These systems appear to be very attractive building blocks for one dimensional nanoscaled organometallic conductive rod networks owing to the excellent ability of the ruthenium system to promote a strong electronic coupling between the metal centers and the conjugated organic ligands. Therefore, we are also interested in electrical transport through these organometallic molecules. Questions of interest include how the current-voltage characteristics of these molecular junctions depend on molecular size, bonding and metal centre architecture.

Our interest is also gradually moving toward the design innovative multifunctional compounds based on redox active carbon-rich organometallics for molecular optoelectronics and spitronics. More precisely, this challenge includes the full conception, realization and analysis of devices. Through experimental and theorical tools, we explore their switching abilities via the tuning of magnetic, optical or electrochemical properties with stimuli such as light or electron transfert.

Collaborations

• Dr. Karine Costuas, Prof. Jean-Yves Saillard (Rennes): Theoretical Calculations

• Dr. Sylvie Choua, Prof. Philippe Turek (Strasbourg, France): EPR Spectroscopy

• Prof. Dan Frisbie (Minneapolis, USA): Current-Voltage Characteristics

• Dr. Corinne Lagrost (Rennes): Surface Modifications / Electrochemistry.

• Dr. Frederic Paul (Rennes): Mixed Ruthenium-Iron Organometallics

• Dr. Thierry Roisnel (Rennes): X ray structures.

Selected publications

• « New paramagnetic ruthenium complexes via one electron reduction of metallacumulenes.»
  S. Rigaut, O. Maury, D. Touchard, P. H. Dixneuf.
  Chem. Commun. 2001, 373.
• « Unprecedented coupling of allenylidene and diynyl metal complexes: a bimetallic ruthenium system with a C7 conjugated bridge.»
  S. Rigaut, J. Massue, D. Touchard, J.-L. Fillaut, S. Golhen, P. H. Dixneuf
  Angew. Chem. Int. Ed. 2002, 41, 4513.
• « Bis-allenylidene Metal Complex and Unique Related Radical with Delocalization of One Electron over Both Trans Carbon-Rich Chains.»
  S. Rigaut, K. Costuas, D. Touchard, J.-Y. Saillard, S. Golhen, P. H. Dixneuf
  J. Am. Chem. Soc. 2004, 126, 4072.
• «Ruthenium Allenylidene Complexes and their Specific Behaviour. »
    S. Rigaut, D. Touchard, P. H. Dixneuf
  Coord. Chem. Rev.  2004, 248, 1585.
• «Bi and Tri Nuclear Ruthenium Carbon Rich Complexes Containing Bis-allenylidene and Mixed Allenylidene-Acetylide Bridges. »
  S. Rigaut, J. Perruchon, S. Guesmi, C. Fave, D. Touchard, P. H. Dixneuf
  Eur. J. Inorg. Chem.  2005, 447.
• «C7 and C9 Carbon-Rich Bridges in Diruthenium Systems: Synthesis, Spectroscopic and Theoretical Investigations of Different Oxidation States.»
  S. Rigaut, C. Olivier, K. Costuas, S. Choua, O. Fadhel, J. Massue, P. Turek, J.-Y. Saillard, P. H. Dixneuf, D. Touchard
  J. Am. Chem. Soc. 2006, 128, 5859.
• « Redox Active Architectures and Carbon-Rich Ruthenium Complexes as Models for Molecular Wires. »
  Stéphane Rigaut, Daniel Touchard, Pierre H. Dixneuf in « Redox Systems Under Nano-Space Control» (Ed : Toshikazu Hirao) Springer : Heidelberg, 2006, pp 55-79.
• « Electronic Communication in “Chain-Like” Trimetallic Ruthenium Complexes with Two C7 Carbon-Rich Conjugated Bridges»
  C. Olivier, S. Choua,  P. Turek, D. Touchard, S. Rigaut
  Chem. Commun  2007, 128,  3100
• «Temperature and Length Dependence of Charge Transport in Redox- Active Molecular Wires Incorporating Ruthenium (II) Bis(s-arylacetylide) Complexes.»
  B. Kim, J. M. Beebe, C. Olivier, S. Rigaut, D. Touchard, J. G. Kushmerick, X.-Y. Zhu, C. D. Frisbie
  J. Phys. Chem. C, 2007, 111, 7521.
• «Redox-Active Molecular Wires Incorporating  Ruthenium (II) s-Arylacetylide Complexes For Molecular Electronics. »
  C. Olivier, B.-S. Kim, D. Touchard, S. Rigaut
  Organometallics 2008, 27, 509.
• «Intramolecular Optical Electron-transfer in Mixed-Valent Dinuclear Iron-Ruthenium Complexes Featuring a 1,4-Diethynylaryl Spacer»
  N. Gauthier, C. Olivier, S. Rigaut, D. Touchard, T. Roisnel, M. G. Humphrey, F. Paul
  Organometallics 2008, 27, 1063.
• «Multifunctional Switches with Carbon-Rich Ruthenium and Diarylethene Units.»
  Y. Liu, C. Lagrost, K. Costuas, N. Tchouar, H. Le Bozec, S. Rigaut
  Chem.Commun. 2008, 6117.