Fully solvable equilibrium self-assembly process: fine-tuning the clusters size and the connectivity in patchy particle systems.

Self-assembly is the mechanism that controls the formation of well-defined structures from disordered pre-existing parts. Despite the importance of self-assembly as a manufacturing method and the increasingly large number of experimental realizations of complex self-assembled nano-aggregates, theoretical predictions are lagging behind. Here, we show that for a nontrivial self-assembly phenomenon, originating branched loopless clusters, it is possible to derive a fully predictive parameter-free theory of equilibrium self-assembly by combining the Wertheim theory for associating liquids with the Flory-Stockmayer approach for chemical gelation.

Metabasin dynamics and local structure in supercooled water.

We employ the distance matrix method to investigate metabasin dynamics in supercooled water. We find that the motion of the system consists in the exploration of a finite region of configuration space (enclosing several distinct local minima), named metabasin, followed by a sharp crossing to a different metabasin. The characteristic time between metabasin transitions is comparable to the structural relaxation time, suggesting that these transitions are relevant for the long-time dynamics.

Relation between local diffusivity and local inherent structures in the Kob-Andersen Lennard-Jones model.

We analyze one thousand independent equilibrium trajectories of a system of 155 Lennard-Jones particles to separate in a model-free approach the role of temperature and the role of the explored potential energy landscape basin depth in the particle dynamics. We show that the diffusion coefficient D can be estimated as a sum over contributions of the sampled basins, establishing a connection between thermodynamics and dynamics in the potential energy landscape framework. We provide evidence that the observed nonlinearity in the relation between local diffusion and basin depth is responsible for the peculiar dynamic behavior observed in supercooled states and provide an interpretation for the presence of dynamic heterogeneities.

Physics of the liquid-liquid critical point.

Within the inherent structure thermodynamic formalism introduced by Stillinger and Weber [Phys. Rev. A 25, 978 (1982)]], we address the basic question of the physics of the liquid-liquid transition and of density maxima observed in some complex liquids such as water by identifying, for the first time, the statistical properties of the potential energy landscape responsible for these anomalies.

Recent results on the connection between thermodynamics and dynamics in supercooled water.

We review recent results on the connection between thermodynamics and dynamics in a model for water. We verify the Adam-Gibbs relation between entropy and dynamic properties using computer simulations, which allow direct access to the relevant properties. We combine experimental measurements of entropy with the Adam-Gibbs hypothesis to predict dynamic properties in deeply supercooled states, which are difficult to access experimentally.

Potential energy landscape equation of state.

Depth, number, and shape of the basins of the potential energy landscape are the key ingredients of the inherent structure thermodynamic formalism introduced by Stillinger and Weber [F. H. Stillinger and T.

Configuration space connectivity across the fragile-to-strong transition in silica.

We present a numerical analysis for SiO (2) of the fraction of diffusive direction f(diff) for temperatures T on both sides of the fragile-to-strong crossover. The T dependence of f(diff) clearly reveals this change in dynamical behavior. We find that for T above the crossover (fragile region) the system is always close to ridges of the potential energy surface (PES), while below the crossover (strong region), the system mostly explores the PES local minima.