Suchergebnisse

In this work a new ultrafast data collection strategy for electron diffraction tomography is presented that allows reducing data acquisition time by one order of magnitude. This methodology minimizes the radiation damage of beam-sensitive materials, such as microporous materials. This method, combined with the precession of the electron beam, provides high quality data enabling the determination of very complex structures. Most importantly, the implementation of this new electron diffraction methodology is easily affordable in any modern electron microscope. As a proof of concept, we have solved a new highly complex zeolitic structure named ITQ-58, with a very low symmetry (triclinic) and a large unit cell volume (1874.6 Å), containing 16 silicon and 32 oxygen atoms in its asymmetric unit, which would be very difficult to solve with the state of the art techniques. ; The authors gratefully acknowledge financial support of European Research Council (ERC-2014-AdG ref 671093 "MATching zeolite SYNthesis with CATalytic activity"), Spanish Government (MAT2015-71842-P (MINECO/FEDER), MAT2012-38567-C02-01 and Severo Ochoa SEV-2012-0267), and Generalitat Valenciana (Project Prometeo). E.M. was also supported by the Italian project FIR2013 Exploring the Nanoworld. ; Peer Reviewed

[EN] In this work a new ultrafast data collection strategy for electron diffraction tomography is presented that allows reducing data acquisition tithe by one order of Magnitude.,,This Methodology minimizes the radiation damage of, beam-sensitive materials, such as microporous materials. This method, combined with the precession of the electron beam, provides high quality data enabling the determination of very complex structures. Most importantly,, the implementation of this new, electron diffraction methodology is, easily affordable in any modem electron Microscope. As a proof of concept, we have solved a new highly complex zeolitic structure named ITQ-58, with a very low symmetry (triclinic) and a large unit cell volume (1874.61(3)), containing 16 silicon and 32 oxygen atoms in its asymmetric unit, which would be very difficult to solve with the state of the art techniques. ; The authors gratefully acknowledge financial support of European Research Council (ERC-2014-AdG ref 671093 "MATching zeolite SYNthesis with CATalytic activity"), Spanish Government (MAT2015-71842-P (MINECO/FEDER), MAT2012-38567-C02-01 and Severo Ochoa SEV-2012-0267), and Generalitat Valenciana (Project Prometeo). E.M. was also supported by the Italian project FIR2013 Exploring the Nanoworld. Authors thank beamline MSPD at Spanish Synchrotron ALBA for beam time allocation. We acknowledge JEOL Japan, JEOL Europe, and specially Junichi Morimoto from JEOL Europe for the assistance during the specific alignments of the microscope. Finally, authors specially thank the Electron Microscopy Service of the Universitat Politecnica de Valencia and, in particular, Manuel J. Planes and Jose L. Moya for their invaluable support for setting up the EDT data acquisition. Original data (collected EDT frames and integrated intensities) can be requested directly from corresponding authors. ; Simancas-Coloma, J.; Simancas Coloma, R.; Bereciartua-Pérez, PJ.; Jorda Moret, JL.; Rey Garcia, F.; Corma Canós, A.; Nicolopoulos ., S. (2016). Ultrafast Electron ...