Hot crystals of thermo-responsive particles with temperature dependent diameter in presence of a temperature gradient

Abstract

Structure formation in non-equilibrium steady state conditions is poorly understood. Non-equilibrium steady state can be achieved in a system by maintaining temperature gradient. A class of cross-linked micro-gel particles, poly-N-isopropylacrylamide (PNIPAM, are reported to increase in size due to adsorption of water as temperature decreases. Here we study thermo-responsive particles with temperature sensitive diameter in presence of temperature gradient, using Molecular dynamics simulation with Langevin thermostat. We find long-ranged structural order using bond order parameters in both cold and hot region of the system beyond a certain diameter ratio of the cold and hot particles. This is due to increase in packing and pressure in both regions. Our observations might be useful in understanding ordered structures in extreme conditions of non-equilibrium steady state.