The Magnetism Network of the Greater Region won the 2018 interregional research prize for its collaborative fundamental research and R&D activities. Congratulations to the coordinator of this organizion, Thomas Hauet. Let’s wish the same success to the French and European Magnetometry Network!
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](https://sites.google.com/site/m3researchgroup/News/newpublicationinthejournaloftheamericanchemicalsocietyonspinstatechemistry/TOC.fr.jpg?attredirects=0)
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
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.
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
En direct des laboratoires de l’institut de Chimie
De nouveaux systèmes « tristables » pour stocker des bits d’information à l’échelle moléculaire
Depuis de nombreuses années, les chercheurs rêvent d’utiliser des molécules bistables comme unités élémentaires pour le stockage binaire de bits d’information (0 ou 1), et ainsi accéder à des mémoires informatiques plus légères et plus petites. Une équipe franco-américaine composée de chercheurs de l’Université de Berkeley, du Centre de Recherche Paul Pascal (CNRS) et de l’Institut de Chimie de la Matière Condensée de Bordeaux (CNRS) vient de réaliser une molécule non plus bistable mais tristable, étendant ainsi les valeurs possibles des bits à 0, +1 et -1. Ces résultats parus dans le Journal of the American Chemical Society ouvrent des perspectives pour le stockage ternaire de l’information qui permettrait d’envisager des mémoires encore plus performantes.
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
Place and date of Birth:
Talence (Gironde, France)
11 Avril 1980
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 24
Fax: +33 5 56 84 56 00
Email: mathieu.rouzieres@crpp.cnrs.fr
| Since 2019 | Assistant Ingénieur en Science des matériaux et Caractérisation, CNRS CRPP, Team M3 |
| 2017 – 2019 | Local contact and member of the comittee of the European magnetometry network for the Université de Bordeaux |
| Since 2016 | Local contact and member of the comittee of the French magnetometry network for the CRPP |
| 2010 – 2019 | Assistant Ingénieur en Instrumentation et Techniques expérimentales, CNRS CRPP, Team M3 |
| 2004 – 20010 | Assistant Ingénieur en Instrumentation, Synchrotron SOLEIL, Ligne de lumière de spectroscopie InfraRouge et TeraHertz AILES |
| 2001 – 2002 | Analyste programmeur (C++, WinDev), European Data |
| 2001 | DUT Mesures Physiques, Université de Bordeaux |
[678]. P. Perlepe, I. Oyarzabal, A. Mailman, M. Yquel, M. Platunov, I. Dovgaliuk, M. Rouzières, P. Négrier, D. Mondieig, E. A. Suturina, M.A. Dourges, S. Bonhommeau, R. A. Musgrave, K. S. Pedersen, D. Chernyshov, F. Wilhelm, A. Rogalev, C. Mathonière, R. Clérac, “Metal-organic magnets with large coercivity and ordering temperatures up to 242°C”, Science, Vol. 370, Issue 6516, pp. 587-592, (2020) – 10.1126/science.abb3861 – Abstract – Reprint – Full text
[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.
[640]. D. Sadhukhan, P. Ghosh, C. J. Gómez-García, M. Rouzieres, Co(II)-Hydrazone Schiff Base Single Ion Magnet Exhibiting Field Induced Slow Relaxation Dynamics, Magnetochemistry, 4, 56 (2018) –10.3390/magnetochemistry4040056
[633]. K. S. Pedersen, P. Perlepe, M. L. Aubrey, D. N. Woodruff, S.E. Reyes-Lillo, A. Reinholdt, L. Voigt, Z. Li, K. Borup, M. Rouzières, D. Samohvalov, F. Wilhelm, A. Rogalev, J. B. Neaton, J. R. Long, R. Clérac, “Formation of the layered conductive magnet CrCl2(pyrazine)2 through redox-active coordination chemistry”, Nature Chemistry, 10, 1056-1061 (2018) – 0.1038/s41557-018-0107-7
| 2019 | Creation of softwares to treat and analize magnetic data (MagSuite) |
| 2017 – 2020 | Conception of a four points inline probe for conductivity measurements for Quantum Design PPMS systems, compatible with air sensitive pellet, and a controlled environment from 400 to 1.9 K, and up to 9T |
| 2015 – 2016 | Improvement of the control & acquisition software of a prototype for visible reflectance measurements, with a controlled environment from 270 to 10 K, and with an adjustable irradiation (365 – 1050 nm) |
| 2013 – 2015 | Integration of helium recondenser on Quantum Design systems (MPMS XL, PPMS) |