Electron Crystallography

Electron Diffraction Tomography

Cry Page Image 1 Electron diffraction tomography (EDT) is a novel technique, which allows single crystal electron diffraction data collections on crystal of size smaller the 1 micron. In our laboratory we have configured a transmission electron microscope Zeiss Libra 120 as a diffraction station for EDT. We are able to collect 3D electron diffraction data on a variety of different materials with the following peculiarities: the diffraction patterns can be collected in energy filtered mode, the diffraction pattern are collected in nanodiffraction mode with a minimum illuminated area of 150 nm in diameter, the patterns can be collected in parallel standard illumination or in precession mode. The data collected in this way are suitable for structure solution and for dynamical structure refinement. Our TEM can be considered then a single crystal diffractometer for nanocrystals.
We are developing specific data collection procedures for making the data collection fully automatic and extremely fast with the idea that sooner or later the TEM should become an automatic diffractometer able to analyze several crystals in one day. A second direction of investigation is the construction of complete data sets by merging 3D data collections coming from different crystals.
 

Low crystallinity and nanodomains 

Cry Page Image 2 Cry Page Image 3 The possibility of collecting 3D single crystal EDT data with a high spatial resolution (150 nm) allows to investigate structural problems which remains obscure for the low crystallinity and the small size of the single crystal domains.
A materials made of ordered domains of few hundreds nm can be studied as a collection of single crystals on which to collect 3D EDT data of structure solution quality. Nanoparticles embedded in a matrix, amorphous or not and crystals with polytypic sequences at the nanoscale can be study in the same way.
For the first time we have the possibility to study the solid state at a scale at which only an average description was available up to now using powder diffraction methods
 
 
 
 
 

EDT on beam sensitive materials

Cry Page Image 4 We have developed a fast EDT procedure that combined with a new generation single electron diffraction camera (MEDIPIX2 detector acquired thanks to a Regione Toscana contribution) allows fast and low dose data collection with dose lower that 0.05 e/(Å-2s). In this way, all the materials described above can be studied with EDT prior to amorphization by the electron beam and on a scale never reached by other diffraction techniques.
 
 
 
 
 
 
 
 
 

Correlative Micro-CT and TEM imaging

Cry Page Image 5 We are developing new transmission electron microscopy methods for the observation of biological samples.
The requirement to have a technique that in the case of pathologies spread on an entire organ or district gives at the same time a global view at low resolution and a local view at ultrastructural level of those regions of interest crucial for understand the pathological mechanisms called for a new correlative imaging method.
We designed a correlation method between X-Ray tomography (Micro-CT, in collaboration with SYRMEP beamline at Elettra - Sincrotrone Trieste) and transmission electron microscopy. Micro-CT is furnishing a global 3D view of the whole organ or tissue with a resolution of few microns, in which it possible to identify specific regions of interest for TEM ultrastructure characterization. The sample can then be cut with the ultramicrotome just across the identified region of interest for obtaining a this section suitable for TEM imaging.
 

Group Members

  • Mauro Gemmi
  • Enrico Mugnaioli
  • Valentina Cappello
  • Arianna Lanza
  • Iryna Andrusenko
  • Francesco Papi
  • Andrea Griesi
  • Fabrizio Campanale

 

Collaborations

  • Prof. Lara Righi Dipartimento di Scienze Chimiche, della Vita e della Sostenibilità Ambientale, Università di Parma.
  • Prof. Luigi Folco Dipartimento di Scienze della Terra, Università di Pisa, Italy.
  • Dr. Lukas Palatinus Czech academy of Science, Prague, Czech Republic.
  • Dr. Tim Gruene PSI, Villigen Switzerland.
  • Ana M. López-Periago, Instituto de Ciencia de Materiales de Barcelona (ICMAB-CSIC), Bellaterra,  Spain
  • Isabella Pigantelli, Université de Lorraine Vandoeuvre-lès-Nancy, France
  • Péter Németh, Institute of Materials and Environmental Chemistry, Research Center for Natural Sciences, Hungarian Academy of Sciences, Budapest Hungary
  • Fernando Rey, Istituto de tecnologia quimica, Valencia Spain.

 

Projects

  • Gliomics project on “Proteomica/genomica/metabolomica per l'individuazione di biomarcatori e lo sviluppo di una piattaforma di rivelazione ultrasensibile in fluidi corporei periferici: applicazione al glioblastoma multiforme”, funded in the PAR-FAS program of Regione Toscana. 
  • Smart@lign project on “Sviluppo di un processo lean per la progettazione web collaborativa e la fabbricazione mediante una tecnologia innovativa di additive manufacturing di allineatori ortodontici personalizzati” funded by Regione Toscana
  • PNRA project on Antarctic meteorites