Activation of a supercooled liquid confined in a nanopore

Abstract

It is well stablished that confinement of supercooled liquids in nano-pores induces various effects as a strong modification of the dynamics and a layering of the local structure. In this work we raise the issue as how these confinement effects are modified when the liquid is out of equilibrium. To answer that question, we use molecular dynamics simulations to investigate the effect of confinement on a supercooled liquid activated by the periodic folding of a molecular motor. We find that the motor opening angle controls the activation of the medium and use that result to study the effect of different activations on the confined supercooled liquid. We observe an increase of the activation effect on the dynamics when the medium is confined. We find that the confinement slowing down dependence with the pore radius depends on the activation of the liquid. We argue that these findings result from a modification of dynamic correlation lengths with activation. In this picture the activation permits to control the liquid correlation length and dynamics inside the pore. Studying the local structure we observe a modification of the layering organization induced by the activation. We also find that the mobility inside the pore depends on the layers, being larger where the local density is small.