Wed 9 Nov 2016 – 2:30*pm (Murdoch University, Senate Room)
Rethinking Structure in Amorphous Materials: From Geometry to Statistics
Peter Harrowell — School of Chemistry, University of Sydney
Despite a long history, there remain many important open questions about, not just the best description of structure in liquids and glasses, but what use these structures provide in terms of understanding the properties of amorphous materials. This talk will introduce the basic questions concerning the role of structure in materials science, how that structure is characterised and then present recent results on how the geometry of the locally stable structures in an amorphous materials influence the stability of the material with respect to crystallization.
A central conclusion of this research is that advances in the study of amorphous structure will involve abandoning the traditional descriptive geometrical approach to structure in favour of regarding structure in terms of the statistical correlations between local structural elements. It is hoped that the description of this exciting open problem will be both accessible to and of interest for mathematicians.
(* Peter’s talk will be at 4pm, but is part of a mini-workshop that starts at 2:30 *)
The nucleation of minerals from ions in aqueous solution underpins important processes from biomineralisation to scale formation and carbon sequestration. All this begins with ion pairing, but what happens next is still a matter that is hotly debated for systems such as calcium carbonate, where the classical nature of nucleation has been called into question [1,2,3]. Therefore it is vital to use both experiment and simulation to fill in the missing details as to how crystalline minerals form. In this presentation we will examine the possible pathways by which two common biominerals, calcium carbonate and calcium oxalate, nucleate in order to try to explain how proteins may influence and control this process. Based on simulation results it will be demonstrated that hard rocks and soft matter are perhaps not as different as they might seem during their earlier stages of formation.