computational materials chemistry
Predicting and designing the structures made by the self-assembly of particles is a key requirement for a new generation of advanced materials. Many fundamental questions are still open. The group’s research involves the computer simulation of complex materials, concentrating on issues of structure and dynamics. All of the projects are done with computational experiments, but all can be done without previous experience of programming.
What is it about the shape of a particle that determines how well it packs?
Some particle shapes fill space better than others, but when they self-assemble, they all try to do the best they can. We have found that particle properties like symmetries, concavity, and aspect ratio all play a role in how dense they can get. But so far we cannot explain why some shapes pack in an unusual complex pattern whereas others are quite simple.
What is the connection between random packings and crystalline packings?
Jammed random packings of particles play an important role in many industrial applications including the stability of mining stockpiles, the safety of pebble bed nuclear reactors, and the stability of amorphous thin films. But the theoretical understanding of these systems is still in its infancy – there is even still wide disagreement on how to define a random packing. Everyone is clear that they are not crystalline, but if you shake them just right, they can become more ordered. This project will investigate in what ways the random packings of a series of different particles are related to the ideal crystal structures of those same particles.
Porous nanoparticle superlattices (with Asaph Widmer-Cooper)
Nanoparticles can now be made with exquisite control of shape and are becoming increasingly important as building blocks for new high-tech materials. Mixtures of particles with directional interactions are attractive candidates for making a new family of porous superlattices, which have applications in catalysis, sensing, and optics. You will explore the range of superlattices that can be made, using Monte Carlo simulations and by extending a structural search algorithm. Interesting structures may be synthesized by collaborators in Japan or the USA.
Building billion year old glass in a day (with Peter Harrowell)
Recent experiments using physical vapour deposition of a warm thin film show that the free surface allows molecules the flexibility to search around a bit before they get stuck. This creates a material which is extremely stable compared to normal bulk glasses, and is equivalent in most respects to a glass which by some estimates has been aged for billions of years. In this project, you will simulate this process and the materials it creates.
For further information, please contact:
School of Chemistry
University of Sydney NSW 2006
Phone: +61 2 9036 7648