Is there a third order phase transition for supercritical fluids?

We prove that according to Molecular Dynamics (MD) simulations of liquid mixtures of Lennard-Jones (L-J) particles, there is no third order phase transition in the supercritical regime beyond Andrew's critical point. This result is in open contrast with recent theoretical studies and experiments which instead suggest not only its existence but also its universality regarding the chemical nature of the fluid. We argue that our results are solid enough to go beyond the limitations of MD and the generic character of L-J models, thus suggesting a rather smooth liquid-vapor thermodynamic behavior of fluids in supercritical regime.

On the existence of a third-order phase transition beyond the Andrews critical point: a molecular dynamics study.

The possibility of the existence of a gas-liquid third order phase transition for fluids is becoming a subject of growing interest. Experimental work suggests its existence for specific systems while recent theoretical models claim its universality. In this work, we employ Molecular Dynamics and investigate the third-order phase transition beyond the Andrews critical point by treating a system of Lennard-Jones particles along three isotherms.

Multiscale approaches and perspectives to modeling aqueous electrolytes and polyelectrolytes.

We review recent work on scale-bridging modeling approaches applied to aqueous electrolytes and polyelectrolytes, connecting the local quantum chemical details to classical statistical and thermodynamics properties. We discuss solvation and pairing of ions in water, ways to include solvent degrees of freedom in effective ion-ion interactions, and coarse-grained simulations of polyelectrolytes including dielectric boundary effects.

Multiscale modelling of mesoscopic phenomena triggered by quantum events: light-driven azo-materials and beyond.

The macroscopic functionality of soft (bio-)materials is often triggered by quantum-mechanical events which are highly local in space and time. In order to arrive at the resulting macroscopically observable phenomena, many orders of magnitude need to be bridged on both the time and the length scale. In the present paper, we first introduce a range of simulation methods at different scales as well as theoretical approaches to form bridges between them.

Multiscale simulation of soft matter: from scale bridging to adaptive resolution.

The relation between atomistic chemical structure, molecular architecture, molecular weight, and material properties is of basic concern in modern soft material science and includes standard properties of bulk materials and surface and interface aspects, as well as the relation between structure and function in nanoscopic objects and molecular assemblies of both synthetic and biological origin. This all implies a thorough understanding on many length and correspondingly time scales, ranging from (sub)atomistic to macroscopic. Presently, computer simulations play an increasingly important, if not central, role.