Position: Ricercatore INFM - TD
Affiliation: INFM SOFT - Physics Dept. University of Rome "La Sapienza", P.le A. Moro 2, 00185, Rome, Italy
Office: Ed. Fermi, Room 43
Telephone: +39 06 4991 3504
Fax: +39 06 4463158
Email: simone.melchionna@roma1.infn.it
Personal Web Page: Click Here
Curriculum Vitae
Publications and Reprints
Research Interests
My work focuses on complex and biological systems investigated via computational methods.
The target systems are typically in the liquid state and range from simple confined fluids, such as Lennard-Jones models,
to proteins embedded in aqueous ionic solutions. In order to deal with the intrinsic multiple spatial and temporal scales of complex phenomena, I take advantage of different elemental simulations techniques, such as Molecular Dynamics, Monte Carlo, Lattice Boltzmann, Density Functional Theory. The development of new algorithms and techniques calls for a unified modelling in Statistical Mechanics, ranging from Gibbs to Boltzmann descriptions applied to microscopic, mesoscopic or macroscopic scenarios.
Current Research Projects
Hydration states is a major actor in stabilizing proteins and DNA in aqueous environments. An interesting class of proteins are the thermophilic ones, which, in contrast to the mesophilic variants, survive in folded structures even above the boiling temperature of water. In our studies we look at the water-exposed surface area, its peculiar corrugation, the population and lifetime of hydrogen bonds, energetics and electrostatic interactions and the overall free energy landscape. Our past work suggests that the specific hydration state enhances macromolecular fluctuations and, at the same time, increases thermal stability.
Typically, colloids and biological polymers show a clear separation of time-scales between degrees of freedom, e.g. heavy solutes in presence of a light surrounding solvent. The hydrodynamic field is modelled at the level of the minimal Boltzmann equation while the solutes follow stochastic molecular dynamics. The mesoscopic descriptions requires handling of thermal noise in the framework of fluctuating hydrodynamics, while atoms and hydrodynamic fields are coupled by momentum balance rules. Alternatively, our numerical schemes allow to directly solve the time-dependent Fokker-Planck equation in order to account for the collisions taking place in liquids.
Related Links
