Análise computacional de dímeros elásticos

Abstract

This study investigates the thermodynamic, dynamic, and structural properties of elastic dimers in core-softened systems using molecular dynamics simulations in the canonical ensemble (NVT). The dimers are modeled as particles connected by harmonic potentials with varying elastic constants, enabling the exploration of how the stiffness or flexibility of the bond influences phenomena such as density anomalies and phase transitions. It is observed that decreasing the elastic constant shifts the Temperature of Maximum Density (TMD) line to higher temperatures and pressures in the pressure-temperature diagram. This behavior is attributed to increased vibrational degrees of freedom, which facilitate the system’s structural adaptation and redistribute thermal energy between vibrational and translational modes. Flexibility also alters the balance between attractive and repulsive interactions, promoting greater compaction under extreme conditions. The simulations include analyses of properties such as heat capacity, radial distribution function, and excess entropy, highlighting the impact of elastic parameters on emergent behaviors. The results underline the relevance of flexible dimeric systems as models for complex liquids, biomaterials, and anisotropic interactions, expanding the study of water-like anomalies in simplified contexts (such as coarse-grained models, and also models that does not consider the electromagnetic part).