In what may be a triumph of rhetoric over conventional scientific language, researchers working with the iconic glassmaker Corning Incorporated recently announced in Chemistry of Materials that they were on the verge of decoding the “glassy genome” in order to improve the industrial production of specialty materials.
The authors are careful to explain that their use of this biochem- ical term aligns with that of the Materials Genome Initiative, a major United States’ undertaking to accelerate the pace of discovery in all branches of materials science. Nevertheless, this colourful analogy to genomic analysis could well confuse some observers about what is going on.
The Corning researchers are not engaged in new experimental procedures, but rather an extensive data-mining exercise. Drawing from decades worth of glass-making records preserved by the company, the paper describes the application of algorithms to this information in order to create more detailed models of glass behaviour. Ideally, the process would make it possible to predict that behaviour well enough to design new types of glass with novel properties and perhaps novel chemical constituents.
This algorithmic approach sits at the empirical end of a spec- trum packed with modelling methodologies that can be applied to understand glass. Along the way to the opposite end are statistical strategies, topological and finite element analysis and atomistic simulations, until you reach the frontiers of fundamental physics, where Dalhousie University chemist Josef Zwanziger tackles glass in a very different way. “I really focus on how the atoms have bonded in glass and what that’s going to do to the optics and mechanics of the glass,” he says. “The kind of modelling that we do is an outgrowth of the atom-scale quantum-mechanical modelling that was developed in the 1980s and 1990s.”
Zwanziger acknowledges that a data-driven study of glass making is bound to be the fastest way to reveal innovations that might become a commercial product, something that obviously interests a corporate giant like Corning. He adds that this accomplishment might not be accompanied by a full understanding of how that innovation works. Nor is this just an academic issue, since it means a manufacturer might run into trouble later on should some major production problem emerge.
Meanwhile, Zwanziger and his colleagues have racked up their own successes by calculating the properties of materials with density functional theory. Over the past decade they have identified prac- tical substitutes for lead in glass, a milestone that eliminates the use of this toxic element while retaining the optical performance it lends to the finished product. That research subsequently revealed how different materials can affect glass’s stress-optic response, which determines the distortion produced as polarized light passes through it. Zwanziger is hoping to extend this work to minimizing the transmission loss in optical fibres. “If you could control the chemistry of the glass properly, we think you could make a glass where that loss of power is virtually zero,” he says. “What that leads to is better fibre optic networks.”
Zwanziger acknowledges that such goals are no less ambitious than what Corning has in mind and there may be no one best way of coming to grips with a material we have been making for thousands of years. “The physics of how glass works is still a really tough problem,” he says.