Dual source high-flux four-circle diffractometer for the determination of complex structures

Equipement, AAP 2017-2

Team: LCPB, Collège de France

Project leader : Marc Fontecave / Victor Mougel

Abstract :

Single crystal diffraction remains today the best tool for the characterization of molecular materials, as it provides a “photographic” picture of the molecule investigated, allowing for structural determination, investigation of redox states, accurate measurement of bond distances and interaction between molecules in the crystalline materials. Diffraction studies are at the heart of porous material studies, and constitute one of the most important characterization techniques for porous molecular materials such as Metal Organic Frameworks (MOFs), but are also critical to the characterization of the molecular precursors utilized for the generation of well-defined porous materials (electrodeposition, sol-gel processes…). The use of single crystal diffractometers has hence become a routine tool for determining the structure of a novel chemical compound, screening a crystal before a synchrotron trip or measuring high resolution data for charge density studies. The recent significant improvements in the development of X-Ray micro-sources presenting higher flux and brilliance and the generalization of detectors with extremely low noise in laboratory single crystal diffractometers now allow to access in the laboratory to data quality that was previously only possible to attain using high-flux instruments equipped with rotating anodes or at synchrotron. These last generation instruments allow not only for a faster structure determination, but open the possibility to study extremely small crystals or highly porous samples with large crystalline cells.

The dual source X-ray diffractometer purchased in the context of this project presents multiple advantages over existing instruments for the characterization of crystalline materials: not only the high X-ray flux will allow lowering the minimum size limit for crystals to be studied, but it will also enable determination of structures for the most challenging applications (MOFs, charge density…). In addition, the instrument will allow for faster structure determination, and allow a high-throughput screening of molecular precursors.

Axes :

Collaboration :