A5028627389- Solid-state spectroscopy and crystallography
- Inorganic Fluorides and Related Compounds
- Crystal Structures and Properties
- Crystallography and molecular interactions
- Nonlinear Optical Materials Research
- Luminescence Properties of Advanced Materials
- X-ray Diffraction in Crystallography
- Glass properties and applications
- Crystal structures of chemical compounds
- Ultrasonics and Acoustic Wave Propagation
- Inorganic Chemistry and Materials
- Crystallization and Solubility Studies
- Acoustic Wave Resonator Technologies
- Ferroelectric and Piezoelectric Materials
- High-pressure geophysics and materials
- Organic and Molecular Conductors Research
- Thermography and Photoacoustic Techniques
- Microwave Dielectric Ceramics Synthesis
- Thermal Expansion and Ionic Conductivity
- Photoacoustic and Ultrasonic Imaging
- Silicon Nanostructures and Photoluminescence
- Winter Sports Injuries and Performance
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Magnetism in coordination complexes
Le Mans Université
2015-2024
Centre National de la Recherche Scientifique
2013-2024
Institut des Molécules et Matériaux du Mans
2015-2024
University of Maine
1986-2024
Université Nantes Angers Le Mans
2013-2021
Institute for Soldier Nanotechnologies
2015
Massachusetts Institute of Technology
2015
University of Sfax
2015
Fluor (United States)
2012
École Centrale Paris
1995
A compact monolayer containing azobenzene has been prepared on silicon substrates. The elaboration route consisted of covalent grafting freshly synthesized moieties onto an isocyanate-functionalized self-assembled (SAM). highly packed and ordered SAM the azobenzene-functionalized were monitored characterized by contact angle measurements X-ray reflectivity (XR). Photoswitching wettability film induced reversible cis-trans isomerization chromophores is experimentally shown from water olive...
Visible photoluminescence (PL) broad bands are observed in the Raman spectra of SiC nanoparticles (np-SiC) with diameters ranging from 10 to 25 nm. The phenomenon is studied versus particle size, chemical composition, annealing, and oxidation treatments. In case quasistoichiometric np-SiC, excitation by 514-nm radiation gives rise red PL emissions mainly enhanced amorphous fraction particles surface disorder induced oxidation. quantitatively analyzed using numerical methods based on cluster...
${\mathrm{NdNiO}}_{3}$ is studied by electron diffraction and Raman scattering, drastic changes are observed at the metal-insulator transition. These features explained in framework of a charge disproportionation nickel, which variance from earlier results, but consistent with recent studies on smaller rare earth nickelates. The spectra insulator phase discussed respect to elpasolite arrangement. It shown that several frequencies directly probe transfer, leads us conclude this parameter...
The cubic-rhombohedral phase transition at 450 degrees C of AlF3 is studied by DSC, X-ray powder diffraction and Raman scattering. It demonstrated that the first order with a hysteresis about 6 degrees. established patterns room temperature space group R3c. A study scattering spectra (that confirms above conclusion) evidences presence two soft modes. shown from theory can be imputed to condensation R5 mode cubic Brillouin zone attribution lines deduced on basis compatibility diagram between...
The combined time-resolved photoluminescence (PL) and theoretical study performed on luminescent [Mo6Br(i)8Br(a)6](2-)-based systems unambiguously shows that their NIR-luminescence is due to at least two emissive states. By quantum chemical studies, we show for the first time important geometrical relaxations occur triplet states either by outstretching of an apex away from square plane Mo6 octahedron or elongation one Mo-Mo bond. Experimental PL measurements demonstrate external environment...
Accurate data, obtained by neutron diffraction, have been used to monitor the first-order reconstructive monoclinic\ensuremath{\leftrightarrow}tetragonal phase transition as a function of temperature both during heating and cooling. Data analysis supports an orientational relationship $[010{]}_{m}\ensuremath{\Vert}[001{]}_{t}$ ${(100)}_{m}\ensuremath{\Vert}{(110)}_{t}$ between tetragonal monoclinic phases. The oxygen atoms evolution in displacive mechanism for transition. Based on these...
2014 Nous reportons l'évolution en fonction de la température des paramètres structuraux (coordonnées et facteurs d'agitation thermique ions) part d'autre transition phase structurale cubique-quadratique dans RbCaF3 à 193 K ainsi que structure ce composé au-dessous 50 K.Ces études ont été réalisées par méthode d'affinement du profil raies diffraction neutrons sur poudre.Le même groupe d'espace (Pnma-D162h) a déterminé 20 4,5 K. L'égalité, basse température, angles rotation octaèdres CaF6...
We report a general and simple approach to take control of the color light-emitting two-luminophore hybrid nanowires (NWs). Our strategy is based on spatial at nanoscale (coaxial geometry) spectral selection two kinds luminophores in order restrict complex charge energy transfers. Thus, it possible photoluminescence (PL) as an interpolation CIE (Commission Internationale de l'Eclairage) coordinates each luminophore. For this purpose, we selected green-emitting semiconducting polymer...
Polycrystalline nickel titanate thin films were deposited on silicon substrates by the radio-frequency (rf) sputtering method using NiTiO3 targets, which in turn sintered from powders obtained solid state reaction. The deposition parameters such as rf-powers, partial pressures of argon and oxygen, well substrate temperatures optimized to ensure homogeneous stoichiometric composition films. Post-synthesis annealing at suitable time durations was realized stabilize ilmenite structure with...
The time-domain Brillouin scattering technique, also known as picosecond ultrasonic interferometry, allows monitoring of the propagation coherent acoustic pulses, having lengths ranging from nanometres to fractions a micrometre, in samples with dimension less than micrometre tens micrometres. In this study, we applied technique depth-profiling polycrystalline aggregate ice compressed diamond anvil cell megabar pressures. method allowed examination characteristic dimensions texturing...
The layer compound RbAlF 4 is shown to undergo structural phase transitions at 553K and 282K under investigation by DSC X-ray powder diffraction. structures of the three phases are determined neutron profile refinement. high-temperature has ideal TlAlF structure P4/mmm which corresponds tilt system a 0 c . intermediate room-temperature confirmed as P4/mbm, + low-temperature consistent with space group Pmmn both p b (near transition temperature) (at very low temperature). non-ferroic while...