Institut Laue Langevin, France
ScientificTracks Abstracts: Struct Chem Crystallogr Commun
Aperiodic composite crystals present long-range order without translational symmetry. These materials may be described as the intersection in three dimensions of a crystal which is periodic in a higher-dimensional space. In such materials, symmetry breaking must be described as structural changes within these crystallographic superspaces. The increase in the number of superspace groups with the increase in the dimension of the superspace allows many more structural solutions. We will present recent results obtained by complementary Laue neutron diffraction and X-ray diffraction techniques on n-nonadecaneurea, a nice illustration of aperiodic materials. Within this original family of alkane-urea composites, we will illustrate how structural phase transitions are characterized by changes of intermodulation and described by increasing the rank of the associated crystallographic superspaces. Recent Publications 1. Zerdane S., Mariette C., Mc Intyre G., Lemée-Cailleau M.H., Rabiller P., Guerin L., Ameline J.C., Toudic B. (2015) Neutron Laue and X-ray diffraction study of a new crystallographic superspace phase in n-nonadecane-urea, Acta Cryst B71, 293-299 2. Toudic B., Rhabiller P., Bourgeois L., Huard M., Écolivet C., Mc Intyre G., Bourges P., Breczewski T., Janssen T. (2011) Temperature-pressure phase diagram of an aperiodic host guest compound, Europhysics Letters 93, 16003-p1-5 3. Braunschweig H., Gackstatter A., Kupfer T., Radacki K., Franke S., Meyer K., Fucke K., Lemee-Cailleau M-H. 4. Uranium Hydridoborates: Synthesis, Magnetism, and X-ray/Neutron Diffraction Structures, (2015) Inorganic Chemistry 54/16, 8022-8028
5. Huesges Z., Lucas S., Wunderlich S., Yokaichiya F., Prokes K., Schmalzl K., Lemée-Cailleau M.H., Pedersen B., Fritsch V., Löhneysen H.V., Stockert O. 6. Evolution of the partially frustrated magnetic order in CePd1-xNixAl; Physical Review B (2017) 96, 1444051-144405-5 7. Szeleg E., Zuzens B., Hawthorne F.C., Pieczka A., Szuszkiewicz A., Turniak K., Nejbert K., Ilnicki S.S., Friis H., Makovicky E., Weller M.T., Lemée-Cailleau M.H. 8. Bohseite, ideally Ca4Be4Si9O24(OH)4, from the Piława Górna quarry, the Góry Sowie Block, SW Poland; Mineralogical Magazine (2017) 81, 35-46.
Marie-Hélène Lemée-Cailleau is expert in phase transition of molecular solids under various external controlled parameters, like temperature, pressure or light. Her speciality is single crystal neutron diffraction, using either monochromatic or polychromatic techniques, as well as X-ray diffraction (table-top or synchrotron), and all related structural analysis. She is physicist in the Science division of the Institut Laue Langevin, the European Neutron Source, located in Grenoble, France, and member of the French and European Crystallographic associations. (orcid.org/0000-0003-4733-4334 ).