Dr. Alessio De Francesco

Office : 103, ILL 22
Phone : +33 4 76 20 79 69   
E-mail : defrance(at)ill.fr

Responsibilities

► IN13 Instrument Co-Responsible

Research Interests

.  Neutron spectroscopy in condensed matter physics
.  Collective dynamics in simple liquids
.  Dynamics in nanoparticle suspensions and confined liquids
.  Bayesian inference and data analysis
.  Dynamics in biological systems

Technical Developments

.  Development of new instrumentation for neutron scattering (ToF spectrometers)
.  Experimental techniques: Neutron spectroscopy, X-ray inelastic scattering.

Computational/theoretical methods

Development of Bayesian approaches and MCMC algorithms for data analysis in neutron and x-ray spectroscopy

Curriculum Vitae

He graduated in Physics in 1997 at the University of Rome 'La Sapienza' with a thesis in Biophysics. He obtained his PhD in Physics at Leeds University in 2002 with a thesis in polymer science.

In 2002, he obtained a post-doctoral position at the University of Perugia and on a biophysical subject, studying the structure and dynamics of hydrated proteins and proteins in solution. This project involved the use of neutron scattering and fostered his interest for this technique. This new interest led him to apply for and obtain in 2004, a 5-year position as researcher for the development and construction of a new spectrometer for inelastic neutron scattering (BRISP) at the neutron source of the Institut Laue Langevin.

In 2005, he became first responsible of the BRISP spectrometer, a position he held until February 2012.

In 2009, he became a permanent researcher at the CNR and joined the IOM Institute in 2010.

In the course of his studies, particularly during his thesis period, he developed expertise in the purification and preparation of biological systems that were then the subject of studies using mainly optical, dielectric and neutron spectroscopy techniques. In particular, he was involved in the study of the dynamics of biological macromolecules and the effect on this of solvent or other perturbing factors.

He then undertook a more focused study of the collective and diffusive dynamics of complex systems, be they biological systems, liquids or nanoparticles suspensions.

More recently, he has devoted a large part of his research in developing Bayesian methods especially dedicated to neutron and x-ray spectroscopy demonstrating the superior ability of these methods in providing a probabilistic and evidence-based modeling of experimental data and avoiding two common opposite risks, overparametrization and confirmation bias.

He is heavily involved in training initiatives concerning the neutron scattering spectroscopy.

Top five publications

.  Physical Review E, 94-2, 2016 doi:10.1103/PhysRevE.94.023305
Bayesian approach to the analysis of neutron Brillouin scattering data on liquid metals
A. De Francesco, E. Guarini, U. Bafile, F. Formisano, L. Scaccia.

.  Physical Review E, 99, 052504 doi: 10.1103/PhysRevE.99.052504
Model-free description of polymer-coated gold nanoparticle dynamics in aqueous solutions obtained by Bayesian analysis of neutron spin echo data.
A. De Francesco, L. Scaccia, R.B. Lennox, E. Guarini, U. Bafile, P. Falus and M. Maccarini

.  ACS Nano, 12-9:8867-8874, 2018 doi:10.1021/acsnano.8b03101
Damping off Terahertz Sound Modes of a Liquid upon Immersion of Nanoparticles.
A. De Francesco, L. Scaccia, M. Maccarini, F. Formisano, Y. Zhang, O. Gang, D. Nykypanchuk, A. H. Said, B. M. Leu, A. Alatas, Y. Q. Cai, A. Cunsolo.
 
.  Nanomaterials, 10-5, 2020 doi:10.3390/nano10050860
The terahertz dynamics of an aqueous nanoparticle suspension: An inelastic x-ray scattering study.
A. De Francesco, L. Scaccia, F. Formisano, E. Guarini, U. Bafile, M. Maccarini, A. Alatas, Y. Q.  Cai, A. Cunsolo.

.  Scientific Reports, 11, 13974, 2021 doi: 10.1038/s41598-021-93452
Searching for a second excitation in the inelastic neutron scattering spectrum of a liquid metal: a Bayesian analysis.
A. De Francesco, U. Bafile, A. Cunsolo, L. Scaccia and E. Guarini