7th European Conference on Molecular Magnetism: Dr. Xiaozhou Ma received the best poster prize

Dr. Xiaozhou Ma received one of two prizes for the best poster presented at the 7th European Conference on Molecular Magnetism which took place in Florence, Italy, the 15th-18th of September 2019.

https://www.ecmm2019.org/

The title of her poster was “Magnetic Exchange Coupling Promotion in Dinuclear Compounds with Redox-active Ligand”.

Xiaozhou Ma was a PhD student of P. Dechambenoit and R. Clérac who defended on the 11th of September 2019.

M3 research has been recently highlighted by the CNRS Institute of Chemistry

This work demonstrates the possibility of modulating the spin state of the FeII sites and subsequently the magnetic properties of a [2×2] FeII grid-like complex by variation of the degree of deprotonation of the hydrazine-based N-H sites of the ligand in the complex. Evidence has been provided, both in the solid state and in solution, towards understanding the strong influence of the spin-crossover process on the pKas of the grid ligands, which exhibit a unique deprotonation pattern. The present study provides a demonstration of the effect of spin state switching of a chemical property, here on ligand pKa in a metallosupramolecular grid.

modulating the spin state of the FeII sites and subsequently the magnetic properties of a [2x2] FeII  grid-like complex

Sébastien Dhers, Abhishake Mondal, David Aguilà, Juan Ramírez, Sergi Vela, Pierre Dechambenoit, Mathieu Rouzières, Jonathan R. Nitschke, Rodolphe Clérac & Jean-Marie Lehn. Spin State Chemistry: Modulation of Ligand pKa by Spin State Switching in a [2×2] Iron(II) Grid-Type Complex J. Am. Chem. Soc. 2018, 140 (26), pp 8218–8227 DOI : 10.1021/jacs.8b03735

See also the Institut de Chimie website of the CNRS

M3 research on MEMS cited by the CNRS Institute of Chemistry

Incorporating functional molecules into sensor devices is an emerging area in molecular electronics that aims at exploiting the sensitivity of different molecules to their environment and turning it into an electrical signal. Among the emergent and integrated sensors, microelectromechanical systems (MEMS) are promising for their extreme sensitivity to mechanical events. However, to bring new functions to these devices, the functionalization of their surface with molecules is required. Herein, we present original electronic devices made of an organic microelectromechanical resonator functionalized with switchable magnetic molecules. The change of their mechanical properties and geometry induced by the switching of their magnetic state at a molecular level alters the device’s dynamical behavior, resulting in a change of the resonance frequency. We demonstrate that these devices can be operated to sense light or thermal excitation. Moreover, thanks to the collective interaction of the switchable molecules, the device behaves as a non-volatile memory. Our results open up broad prospects of new flexible photo- and thermo-active hybrid devices for molecule-based data storage and sensors.

Incorporating functional molecules into sensor devices is an emerging area in molecular electronics

Matias Urdampilleta, Cedric Ayela, Pierre-Henri Ducrot, Daniel Rosario-Amorin, Abhishake Mondal, Mathieu Rouzières, Pierre Dechambenoit, Corine Mathonière, Fabrice Mathieu, Isabelle Dufour et Rodolphe Clérac
Molecule-based microelectromechanical sensors
Scientific Reports – Mai 2018
DOI: 10.1038/s41598-018-26076-2

See also the Institut de Chimie website of the CNRS

M3 research on Redox-Active ligand to promote spin delocalization cited by the CNRS INC

A new multi-switchable complex has been rationally assembled using a redox-active and strongly complexing bridging ligand. By simple oxidation/reduction, its magnetic properties can be tuned from a spin-crossover complex, to a single-molecule magnet with an S = 5/2 spin ground state (when once reduced) and to diamagnetic species when twice reduced. This work illustrates experimentally and theoretically how successive redox processes can increase the spin delocalization, and thus promote a dramatic enhancement of the intramolecular magnetic coupling through a bridging ligand, not only in its radical form. This general synthetic approach should help for the intentional design of new high-spin complexes and SMMs, but it could also be extended to systems with higher nuclearities and dimension- alities, for example to obtain high-temperature molecule- based magnets.

Xiaozhou Ma, Elizaveta A. Suturina, Siddhartha De, Philippe Négrier, Mathieu Rouzières, Rodolphe Clérac et Pierre Dechambenoit
Redox-Active Bridging Ligand as a Tool to Promote Spin Delocalization, High Spin Complexes and Magnetic Multi-Switchability
Angewandte Chemie International Edition – Avril 2018
DOI: 10.1002/anie.201803842


See also the Institut de Chimie website of the CNRS

Dr. Pierre Dechambenoit

Maître de Conférences / Associate professor, University of Bordeaux – IUT HSE (EH&S)

Place and date of Birth:
Mulhouse (Haut Rhin, France)
25 Mars 1982
Institutional address:
Centre de Recherche Paul Pascal
CRPP – CNRS UMR5031
Research team M3
115, avenue du Dr. A. Schweitzer
33600 Pessac, France

Phone:     +33 5 56 84 56 71    
Fax:         +33 5 56 84 56 00
Email:      pierre.dechambenoit@crpp.cnrs.fr

orcid.org/0000-0001-7850-2260

Academic degrees

2008Ph. D. at the University Louis Pasteur in Strasbourg, Prof. M. W. Hosseini and Dr. S. Ferlay
2005DEA of Transition Metal Chemistry and Molecular Enineering, Mention Bien (Strasbourg)
2003 – 2004Licence and Maitrise of Chemistry (Strasbourg)
2001 – 2002DEUG in Science of the matter, Mention Très Bien (1st) (Strasbourg)

Previous positions

2009 – 2010 Post-doctoral Research Associate at the University of California Berkeley, (USA), Prof J. R. Long

Publications

Author or co-author of 48 research papers published in refereed journals (h factor = 19).

Significant publications

[665]. X. Ma, E. A. Suturina, M. Rouzières, F. Wilhelm, A. Rogalev, R. Clérac and P. Dechambenoit “A heteroleptic diradical Cr(III) complex with extended spin delocalization and large intramolecular magnetic exchange”, Chem. Commun., 56, 4906-4909, (2020) – 10.1039/d0cc00548g

[658]. Y.S. Ye, X.Q. Chen, Y. De Cai, B. Fei, P. Dechambenoit, M. Rouzières, C. Mathonière, R. Clérac and X. Bao “Slow Dynamics of the Spin-Crossover Process in an Apparent High-Spin Mononuclear FeII Complex”, Angew. Chem. Int. Ed., 58, 18888-18891, (2019) – 10.1002/anie.201911538.

[647]. X. Ma, E. A. Suturina, M. Rouzières, M. Platunov, F. Wilhelm, A. Rogalev, R. Clérac, P. Dechambenoit, Using Redox-Active π Bridging Ligand as a Control Switch of Intramolecular Magnetic Interactions, J. Am. Chem. Soc., 141, 7721-7725 (2019) – 10.1021/jacs.9b03044