Melting Scenario for Coulomb-interacting Classical Particles in Two-dimensional Irregular Confinements

The `melting' of self-formed (solid-like) rigid structures made of small number of interacting classical particles confined in a irregular two-dimensional space has been investigated using Monte Carlo simulations. We will show in the talk that the interplay of long-range Coulomb repulsions between these particles and the irregular confinement yields a solid-like phase at low temperatures that possesses a bond-orientation order but the positional order is depleted down to the lowest temperatures. Upon including thermal fluctuations, this solid-like phase would smoothly cross over to a liquid-like phase by destroying the bond-orientation order. The demise of solidity is aided by the proliferation of disclinations. We will discuss the behavior of different physical observables across the crossover region. Our results will be shown to help quantifying melting found in experiments on systems with confined geometries.