Reprinted from the April 2001 edition of the Mössbauer Spectroscopy Newsletter, published as part of Volume 24, Issue 4 of the Mössbauer Effect Reference and Data Journal
The French group of Mössbauer spectroscopy, GFSM, was founded in 1979 and links a community of approximately 50 scientists (chemists, physicists, biologists, and geologists) working in about 30 different laboratories. The eight members of the scientific committee are each elected for a period of three years. The objectives of the GFSM are to promote the exchange of scientific and technical information amongst its members and to help train young scientists. The group is currently examining ways of establishing stronger ties with other Mössbauerists outside the country, and in particular with those belonging to French-speaking communities.
The main event of the GFSM is the annual meeting, which is usually held in May. It moves between the different groups, so enabling the members to become more familiar with the interests and infrastructure of the different laboratories. Moving around France also enables the members to sample the different gastronomic pleasures of the various regions. The two-day meeting consists of oral presentations, a poster session, a display of scientific equipment, and a visit to the local laboratory and to adjacent large-scale facilities (for example, the Intense Pulsed Field Laboratory at Toulouse, the Heavy Ion Accelerator at Caen). During a meeting, both the topic and the site of the next meeting are decided by the assembly following suggestions made by the different groups. The scientific content of the meeting is then refined by the organising group in conjunction with the scientific committee.
In the past, the meetings have concerned specific “hot” topics (spin electronics, magnetic multilayers, high Tc superconductors, relaxation phenomena, etc.) as well as themes for which the use of Mössbauer spectroscopy could be developed further (biology, semiconductors, etc.). For the latter, the group invites specialists from outside the Mössbauer community. Time is also generally available for the discussion of material problems and for exchanging information (new instrumentation, experimental equipment, data fitting procedures, synchrotron radiation, etc.). A special emphasis is placed on the contribution of Ph.D. students and post docs, who are encouraged to present their work and who receive subsidies to attend the meeting. An annual prize is presented for the best thesis involving Mössbauer spectroscopy.
The next annual meeting will take place on the 17th and 18th of May in Rouen in Normandy (where, in 1431, 19-year-old Jeanne d’Arc was burnt at the stake) and it will center on the theme of “developing materials in the fields of Physics, Chemistry and Biology.” On the 16th of May, a one-day course has been organized for those who wish to be introduced to Mössbauer spectroscopy and to learn how it may be of use in their particular line of research.
Further information will soon be available at the Web site, currently under construction.
Mössbauer Spectroscopy in France
In the response to a general call for information on the current Mössbauer research that is taking place in France, the following reports were received by the Mössbauer Effect Data Center.
Commissariat à l’Energie Atomique – Saclay
Gif-sur-Yvette Cedex
Names and Titles of Researchers
Dr. Pierre Bonville
Dr. J. A. Hodges
History and Areas of Research
Mössbauer spectroscopy started in Saclay in 1962 when Pierre Imbert began his thesis work on “The study of dispersion phenomena linked with the recoilless absorption of atomic nuclei” under the direction of Alfred Kastler, Nobel Laureate in Physics. His first task was to design and develop the drive and detection systems for the spectrometer. Shortly afterwards, a cryostat suitable for Mössbauer spectroscopy was designed and built. The local development of equipment, in particular that of cryostats allowing measurements to progressively lower temperatures, remained one of the interests of the group.
The 57Fe measurements that followed (both for absorbers and sources) related to the magnetic properties of various compounds and included the study of magnetic relaxation phenomena. Other Mössbauer isotopes were also used, in particular a number belonging to the rare earth series. Recent work has involved 57Fe, 117Sn, 151Eu, 155Gd, 161Dy, 166Er, 169Tm, and 170Yb. In addition to the standard cryostats enabling measurements down to 1.4 K, two 3He/4He dilution refrigerators are operational and provide base temperatures below 30 mK. Magnetic fields up to 7 T may be applied. The group comprises two scientists and two technical assistants. There are presently no visitors or Ph.D. students.
The following lists some recent and ongoing research projects.
Search for quantum tunneling in nanoparticles
Superparamagnetism in nanoparticles
Heavy Fermion behavior in Yb based alloys
Commensurate/incommensurate magnetic ordering in rare earth intermetallics
Magnetic properties of intermetallic and cuprate superconductors
Vortex lattice properties of high Tc superconductors
Properties of geometrically frustrated systems (spin-liquid and spin-ice phases)
Some of these studies are carried out in collaboration with the Grenoble Mössbauer Group and with colleagues from the muon spectroscopy and neutron diffraction/diffusion communities.
Commissariat à l’Energie Atomique – Grenoble
Grenoble Cedex
Names and Titles of Researchers
Magnetism:
Jean-Pierre Sanchez, Deputy Director, CEA–Grenoble Paul Vulliet, Associated Professor, Grenoble University |
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Biology: Jean-Louis Oddou, Associated Professor, Grenoble University Claudine Jeandey, Researcher, CNRS |
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Pierrette Auric |
Nanostructures:
Pierrette Auric, Associated Professor, Grenoble University |
Areas of Research
At CEA–Grenoble, three laboratories are involved in Mössbauer spectroscopy:
• Magnetism
The study of the magnetic and electronic properties of strongly correlated electron systems is the main subject of interest of Jean-Pierre Sanchez and Paul Vulliet. Special attention is paid to rare earth and actinide compounds, to the development of high-pressure facilities, and the use of less common Mössbauer isotopes.
• Biology
Mössbauer spectroscopy under external applied magnetic field is used by Claudine Jeandey and Jean-Louis Oddou to study the electronic structure of heme and non-heme iron protein sites, and to characterize the intermediate species which appear during enzymatic cycles (by coupling Mössbauer and freeze-quench techniques). The whole natural system will be also considered by studying, with Mössbauer spectroscopy, the way some iron proteins operate in vivo.
• Nanostructures
CEMS is mainly used by Pierrette Auric for surface and interface investigations of iron nanoparticles and multilayers with potential application in perpendicular magnetic recording.
Laboratoire de Physique de l’Etat Condensé
Université du Maine
Le Mans Cedex
Names and Titles of Researchers
Jean-Marc Greneche, Researcher – CNRS |
Areas of Research
The Mössbauer group at the Laboratoire de Physique de l’Etat Condensé of the University of Le Mans (as a CNRS-joined research laboratory) is composed of five permanent researchers and professors, one technician, one post-doctorate fellow, and two to three students. Numerous visiting scientists (approximately four to six per year for one to three months each) are working at the laboratory through various exchange scientific programs with Poland, Slovakia, Spain, Algeria, Colombia, Ireland, and others. The laboratory possesses both experimental facilities (four spectrometers allowing 2K-1000K 57Fe transmission Mössbauer experiments and in-magnetic field measurements (0–9T) to be performed) and computing facilities (35 biprocessors PC cluster).
The main activities are focused first on the magnetic properties of amorphous magnetic materials, magnetic nanomaterials including nanoparticles, nanostructured powders and nanocrystalline alloys (surface and interface effects), iron-based fluoride materials (frustration), and then on numeric modeling of magnetic properties of low dimensional magnetic systems based on computer simulations.
Laboratoire de Magnétisme et Applications
Groupe de Physique des Matériaux
Université de Rouen
Mont-Saint-Aignan Cedex
The Laboratoire de Magnétisme et Applications (LMA) is a part of the Groupe de Physique des Matériaux, UMR CNRS 6634, associated with CNRS, Université de Rouen, and INSA de Rouen (engineering school). Among the 15 people of the LMA, nine are especially concerned with Mössbauer spectrometry.
Names and Titles of Researchers
Jacques Teillet, Professor, Head of the Team
Abdeslem Fnidiki, Professor Jean-Marie Le Breton, Assistant Professor Fabienne Richomme, Assistant Professor Jean Pierre Lebertois, Technician Gael Khelifati, Student Rodrique Larde, Student Antoine Morel, Student Thomas Verdier, Student |
Areas of Research
The LMA is concerned with microstructural (SEM, TEM, atom probe), structural (X-rays), magnetic (VSM, SQUID), and local (Mössbauer) analyses of magnetic materials and with associated numerical simulations. Aging and swift ions irradiation effects are particularly emphasized.
Present research is concerned with metallic magnetic nanomaterials:
Multilayers (Fe/rare earth, Fe/transition metal, magnetoresistive and magnetostrictive ML).
Analysis of interfaces by selective deposition of 57Fe monolayers. Irradiation or annealing effects. Anisotropy results are explained using an electronic hybridization model.
Nanograins by mechanical alloying (Fe-Cr alloys, hydrogen reactive alloying of NdFeB magnets, magnetoresistive nanograins).
Partially nanorecrystallized amorphous ribbons (finemet-type).
Hard magnets (oxidation, spring-magnets, new hexaferrites).
The laboratory possesses transmission Mössbauer spectrometers (TMS) ranging from 2K to 1000K, high field TMS (to 11 Tesla), and home-made CEMS (20-500K). The LMA has published approximately 40 articles in international journals dealing with the Mössbauer effect since 1998.
Laboratoire d’Analyse Spectroscopique et de Traitement de Surface des Matériaux
Université de Rouen
Mont-Saint-Aignan Cedex
Names and Titles of Researchers
Dr. Béatrice Hannoyer, Professor
Dr. François Petit, Maître de Conférence Dr. Samuel Jouen, Post-Graduate Dr. Malick Jean, Maître de Conférence Names and Titles of Researchers (Continued) Dr. Virginie Nivoix, Maître de Conférence Dr. Raphaële Danoix, Maître de Conférence |
Areas of Research
The laboratory specializes in the spectroscopic analysis of the oxides of transition metals. These oxides are inorganic compounds studied for their structure-property relationships or oxides grown on metal surfaces. The analytical methods are non-destructive methods, among which appear notably optical methods.
The Mössbauer group plays a part in the following areas:
Study of the chemical bound (ferrites, manganites, hexaferrites)
Search for ways of synthesis allowing to improve some characteristics
Characterization of oxides in the form of thin films
Study of metal-ceramic interfaces
High temperature oxidation of metals (iron and tin alloys)
Atmospheric corrosion (iron and tin alloys)
The team consists of 11 teaching researchers, two post-graduates, and one technician under the direction of Béatrice Hannoyer. The laboratory possesses three spectrometers, three 3 e-conversion detectors, 10K to 1000K, and 57Fe, 119mSn.
Laboratoire de Chimie Physique et Microbiologie pour l’Environnement
Université Henri Poincaré-Nancy I
Villers-lès-Nancy Cedex
The Laboratory of Physical Chemistry and Microbiology for Environmental Science (LCPME), a mixed laboratory between CNRS and the University Henri Poincaré of Nancy, and managed by Dr. J.-J. Ehrhardt, incorporates a group of researchers working with Mössbauer spectroscopy techniques. Among them are:
Names and Titles of Researchers
J.-M. R. Génin, Professor
J.-C. Block, Professor F. Jorand, Asst. Professor M. Mullet, Asst. Professor C. Ruby, Asst. Professor Dr. M. Abdelmoula, Engineer Dr. O. Benali, Visiting Scientist B. Appenzeller, Graduate Student S. Boursiquot, Graduate Student A. Géhin, Graduate Student G. Ona-Nguema, Graduate Student |
History and Areas of Research
Mössbauer techniques were introduced in LCPME by moving the former Laboratory of Mössbauer Spectroscopy in Materials Science of the University of Nancy 1 in 1986. Main fields of interest thus shifted from physical metallurgy and steel properties (Fe-C, Fe-N, martensite, austenite, bainite, and iron-based alloys) and magnetism (iron-rare earth alloys) towards the corrosion of iron and steels. Presently, it is essentially concerned with the reactivity of iron species in environmental science, mineralogy, and biogenesis of iron minerals. A major and continuing topic has been the study of iron(II-III) double layered hydroxysalts (green rusts, GR) that incorporate anions such as Cl-, SO42-, CO32-. Their role in the corrosion process of steels and the development of corrosion inhibitors, e.g. phosphate, nitrite, is enhanced. But the discovery of a new mineral in hydromorphic soils – identified as a GR in 1996 – gave an impetus towards soil science. The potential of using GRs for reducing pollutants such as nitrate, chromate, and selenate is considered. In situ Mössbauer monitoring of Fe(II-III) species in the field is in course with the miniaturized spectrometer developed by G. Klingelhöfer of Mainz. Bioreduction of ferric lepidocrocite into GR by dissimilatory iron reducing bacteria was recently successful and many collaborations concerning clay minerals are under way. Other problems relative to sulfide minerals are also investigated.
Université Bordeaux I
Pessac Cedex
Names and Titles of Researchers
Léopold Fournes, University Professor, Scientific Adviser, and Technical Manager
Alain Wattiaux, Research Engineer, CNRS, Scientific Adviser, and Technical Manager
Areas of Research
Study of high oxidation states and electronic shell configurations in iron oxides.
Study of fluorides and oxyfluorides of iron, tin, and antimony.
Study of uranium, rare earth, or transition element-based intermetallics.
Use of an in situ cell to follow, by Mössbauer resonance: solid-reactions, modification of iron-based electrodes during electrochemical cycles.
Related Materials
Oxides
Halides
Hybrid materials
Metals
Available Equipment
Mössbauer Spectrometer (4) (Gamma Nuclear Resonance)
Useable radioactive sources: 57Co, 119Sn
Analysis as a function of temperature (4.2-800K): In situ apparatus (solid-gas reactions)
Electrochemical equipment (potentiostat + electrochemical cells): In situ measurements
Applications and Industrial Concerns
In situ study of the discharging lithium batteries
Catalytic processes
Chemical and electrochemical industries (batteries)
Collaborations
Laboratoire de Science et Génie des Matériaux Métalliques, École des Mines, Nancy
Laboratoire de Physico-chimie des Matériaux et Laboratoire de Chimie Minérale D, Montpellier
Service de Physique, MDIH, CEN-Grenoble
Laboratoire d’Archéologie des Métaux, Jarville la Malgrange
Institut de Synthèse et d’Étude des Matériaux (ISEM) et Département d’Électricité et d’Électronique, Université du Pays-Basque, Bilbao (Spain)
Département des Sciences Chimiques et Biologiques de l’Université de Lisbonne (Portugal)
Laboratoire d’Etudes des Matériaux en milieux agressifs de la Rochelle
Equipe Matériaux Moléculaires et Biomimétiques
Laboratoire de Chimie de Coordination du CNRS
Université Paul Sabatier
Toulouse Cedex
Names and Titles of Researchers
Jean-Pierre Tuchagues, Professor
Azzedine Bousseksou, Chargé de Recherche au CNRS Jean-Pierre Costes, Chargé de Recherche au CNRS Marie-Hélène Darbieu, Ass. Professor Pascal La Croix, Chargé de Recherche au CNRS Jean-Pierre Laussac, Directeur de Recherche au CNRS Ph.D. and Post-Doctoral Students: 7 |