Theoretical Soft Matter Group

One of the most famous challenges in biology that, despite huge effort, remains open is the mechanism that regulates the folding of proteins. Significant progresses have been made recently, also thanks to theoretical and computational methods. With such techniques, our group studies the thermodynamic features of protein folding using all-atoms as well as coarse-grained models relying on polymer theory.

Other phenomena that our group investigates are related to entropy-driven ordering. In particular, highly elongated objects are known to show a very rich behaviour in terms of competition between order and disorder in their positions and orientations. Depending on the shape of the objects and on the external conditions, nematic and cholesteric phases appear. If the objects have a helical shape, a screw-like phase can appear, a phase that our group has investigated in detail.

One more topic that we investigate is another class of biological polymer, the nucleic acids (DNA and RNA). We study such polymers at different length scales, starting from large double-helical objects that condensate into toroidal or stick phases, to a coarse-grained nucleotide-level representation using the oxDNA model. This model allows to study small systems (less than 50 base pairs) in great detail, and extract thermodynamic, dynamic and structural information that is impossible to access in experiment. On larger systems,  thanks to the advances in GPU computer processing, mechanical and structural properties can be investigated for objects as large as a full-scale DNA origami.

One more class of systems that we investigate is the formation of structures such as membranes, micelles and vesicles from a full-atom perspective. In particular, we try to predict which properties the solvent and solute molecules need to have to be able to form layers or bilayers in an environment different from water, such as the one present on far away celestial bodies (i.e., the jovian moon Titanus) that lack water but do possess lakes of other materials in liquid form.

Finally, we investigate the collective behaviour of non-isotropic particles in terms of the formation, through self-assembly, of a target structure. Our research in this direction tries to understand which are the key properties that a microscopic object, such as a colloidal particle, must posses in order to form spontaneously a specific target structure. Extracting general properties is a challenging process, and our group has been one of the most active in this research line.