The role of attraction in the phase diagrams and melting scenarios of generalized 2D Lennard-Jones systems.

Monolayer and two-dimensional (2D) systems exhibit rich phase behavior, compared with 3D systems, in particular, due to the hexatic phase playing a central role in melting scenarios. The attraction range is known to affect critical gas-liquid behavior (liquid-liquid in protein and colloidal systems), but the effect of attraction on melting in 2D systems remains unstudied systematically. Here, we have revealed how the attraction range affects the phase diagrams and melting scenarios in a 2D system.

Complex crystalline structures in a two-dimensional core-softened system.

A transition from a square to a hexagonal lattice is studied in a 2D system of particles interacting via a core-softened potential. Due to the presence of two length scales of repulsion, different local configurations with four, five, and six neighbors are possible, leading to the formation of complex crystals. The previously proposed interpolation method is generalized to calculate pair correlations in crystals whose unit cell consists of more than one particle.

The behavior of benzene confined in a single wall carbon nanotube.

We present the molecular dynamics study of benzene molecules confined into the single wall carbon nanotube. The local structure and orientational ordering of benzene molecules are investigated. It is found that the molecules mostly group in the middle distance from the axis of the tube to the wall.

Repulsive step potential: a model for a liquid-liquid phase transition.

In the framework of the perturbation theory for fluids we study the model with the isotropic repulsive step potential which in addition to the hard core has a repulsive soft core of a larger radius. It is shown that this purely repulsive potential is sufficient to explain a liquid-liquid phase transition and liquid anomalies.