Structure and phase transitions of two-dimensional core-softened colloidal dumbbells: a molecular dynamics study

摘要: Formation of two-dimensional (2D) quasi-crystalline structure by colloidal dumbbells interacting via a core-softened potential is studied using molecular dynamics simulations. Owing to the presence two length scales associated with rigid bond dumbbell and minimum repulsive force well, system exhibits rich complex 2D patterns ranging from low-density triangular ordered lattice, coupled stripe-ordered lattice structure, hexagonal Kagome patterns, high density clusters as increases. At very density, form compact lattice. We have also identified order-to-disorder transition temperature at which phase transitions disordered examining energy, heat capacity radial distribution functions system. In addition dimeric dumbbells, we structures formed monomeric spheres that interact through same potential. found although can produce most quasi crystalline for system, there are notable differences. The interplay spatial present in unique stripe-triangular intermediate densities not observed particles. disparity between lengths has effect disrupting formation regular leading irregular defective hexagons lattices. This study shows scales, be utilized generate demonstrates building blocks creating structures.