Waterlike features, liquid–crystal phase and self-assembly in Janus dumbbells

•Molecular dynamics simulations of Janus nanoparticles.•The monomeric system do not have anomalies, but density and diffusion anomalies were observed for the Janus dumbbells.•Distinct self-assembled structures obtained depending on density and temperature.•Liquid–crystal phase.

We explore the phase diagram of Janus nanoparticles using Molecular Dynamics simulations. Each monomer in the dimer has distinct characteristics. One type of monomer interacts by a Lennard Jones potential, while the other type interacts through a two length scale potential. Previous studies for the monomeric system using this specific two length scale potential do not indicate the presence of waterlike anomalies. However, our results show that the combination of two length scales potential and LJ potential in the Janus nanoparticle will lead to thermodynamic and dynamic anomalies. The self-assembly properties were also explored. We observe distinct kinds of self-assembled structures and a liquid–crystal phase. This result indicates that it is possible to create Janus nanoparticles with waterlike features using monomers without anomalous behavior. The anomalies and structures are explained with the two length scale potential characteristics.