Speaker: Dr. Partha Pratim Das, NanoMEGAS SRL, Rue Émile Claus 49, bte 9, 1050 Brussels, Belgium.
Seminar Topic: “Electron Diffraction for Structural Characterization of Nanocrystalline Materials”
Date & Time: Tuesday, 25th August 2026, at 4:00 PM
Venue: AG-09/11 Lecture Hall, SSCU
Abstract:
Electron diffraction in the transmission electron microscope (TEM) enables crystallographic analysis of individual nanometer-sized crystals using minute amounts of material. This presentation will highlight applications of three-dimensional electron diffraction (3DED/MicroED), combined with beam precession to reduce dynamical diffraction effects, for the structural characterization of a broad range of materials, including zeolites, pharmaceuticals, pigments, minerals, and corrosion products.
For highly beam-sensitive materials, radiation damage remains a major limitation. We therefore introduce a serial electron diffraction approach combined with beam precession, where data from many individual crystals are merged for structure solution. This minimizes the dose per crystal, avoids crystal tilting, and can be implemented on conventional TEMs. Recent results on beam-sensitive and hydrated materials susceptible to beam and vacuum damage will also be presented.
References:
1. E. van Genderen, M. T. B. Clabbers, P. P. Das et al., Acta Crystallogr. A 72 (2016) 236–242.
2. J. I. Tirado, A. Sala, A. Bordes, P. P. Das, et al., Angew. Chem. Int. Ed. 64 (2025), e202416515.
3. N. Zacharias, F. Karavassili, P. Das, et al., Microchemical Journal 138 (2018) 19–25.
About the Speaker:
Dr. Partha Pratim Das is an Application Scientist at NanoMEGAS SPRL, Belgium. He received his M.S. degree in Chemical Sciences from the Indian Institute of Science (IISc), Bangalore, India, where he worked under the supervision of Prof. T. N. Guru Row as part of the Integrated Ph.D. program. He subsequently obtained his Ph.D. in Materials Science from ETH Zurich, Switzerland, in 2012 under Prof. Hans Beat Bürgi and Prof. Anthony Linden. His doctoral research focused on modeling diffuse scattering from single-crystal X-ray diffraction data to understand structural disorder in crystalline materials.
He joined NanoMEGAS in 2012 and has since played a key role in the development and application of precession-assisted three-dimensional electron diffraction (3D ED/MicroED) for structure determination of nanocrystalline materials, including pharmaceuticals, zeolites, covalent organic frameworks (COFs), complex minerals, and cultural heritage materials, including studies of corrosion-related structural changes.
His current research focuses on Serial Electron Diffraction (SerialED) for beam-sensitive materials and electron pair distribution function (ePDF) analysis of amorphous and nanocrystalline materials. He has authored or co-authored more than 50 peer-reviewed publications, organized or co-organized over 30 international workshops and training schools, co-supervised a Ph.D. student at ITQ Valencia, and served as an external examiner for doctoral theses in electron diffraction.