Simulation of Organic Crystal Networks

Quite often complex fluids exhibit solid-like behavior due to the formation of networks by the suspended particles. A jammed state is achieved wherein the motion of the suspended particles tends to cease. Such solid-like behavior can also be achieved at very low concentrations for aspherical particles, where the networks are formed due to excluded volume and short-range attractions. However, such particulate networks tend to exhibit brittleness on the slightest of the disturbance, thus irreversibly transitioning to liquids at the same conditions of concentration, ambient temperature and pressure.

The nature of the particles, their interparticle interactions and their interaction with the surrounding fluid seem to be the deciding factors for such temporary, brittle solid-like behavior and the conditions for their collapse. This work attempts to investigate and characterize the effect of particle properties such as size and aspect ratio, and interparticle forces on the rheological properties of such particulate networks. The experimentally observed solid packings of aspherical particles are simulated as a three dimensionally periodic jammed network of randomly oriented ellipsoids. Further, their breakdown is simulated under various external disturbances and the conditions for the simulated collapse are compared with the experimental observations for an equivalent system.