«Structure and Local Order in Porous Solids: Insights from Powder Diffraction & Solid-state NMR»

El próximo martes 12 de Noviembre a las 12:00 horas en el salón de Actos del ITQ tendrá lugar la charla titulada «Structure and Local Order in Porous Solids: Insights from Powder Diffraction & Solid-state NMR«, impartida por Charlotte Martineau, del Institut Lavoisier de Versailles (ILV) & Université de Versailles St.Quentin en Yvelines (UVSQ)

Structure determination of hybrid solids from powder diffraction data only is still a challenge, representing a barrier for a better understanding of their properties. Solid-state nuclear magnetic resonance (NMR), which provides a point-of-view complementary to that of diffraction, has emerged as a particularly well-suited technique to face this challenge. Crystallography by a joint diffraction and NMR approach however requires adapted methods for measurements and data analysis. The first part of the talk focuses on recent methodological and instrumental developments in solid-state NMR, necessary to get resolution of all the structural features of a solid. In particular, the effects of multiple-resonance decoupling and new NMR experiments are presented. These techniques yield one and two-dimensional NMR spectra with unprecedented resolution, revealing fine details about short and long-range order in hybrid solids. The second part of the talk shows how NMR data can be included during the structure resolution process, from space group determination to building of an initial model and refinement. Finally, the high sensitivity of the NMR spectra to local order is illustrated for hybrid solids. It allows going beyond strict periodicity by providing information about the non-periodic sub-networks of crystals, host-guest interactions, dynamic, structure modifications occurring during dehydration/rehydration in these materials… http://www.ilv.uvsq.fr/perso/martineau/