Grant: Research Tools and Instruments - Category 1 (<$150,000)

Solids can display structural disorder at long-range (crystal), mesoscopic (inter-unit cell), and local (atom) length scales. Changes to structural periodicity can have a dramatic influence on a material's physical properties and reactivity, and it can offer valuable insights into material formation pathways in many geogenic and biogenic materials. Nevertheless, the measure and modeling of intermediate-range disorder in non-glassy solids is extremely understudied. This knowledge gap has catalyzed a collaboration at Memorial University that combines experimental and computational simulation expertise related to structural disorder in materials: * synthesis and structural characterization of solid materials (Dr. K. Poduska), and * computational studies of crystallinity and crystallization in glasses (Dr. I. Saika-Voivod). Together, we are working to correlate differences in mesoscopic atomic order with changes in vibrational spectra of solid materials. To do this, we require new research instrumentation (a far-infrared spectromicroscope) to investigate low-energy phonon modes that are characteristic of inter-unit cell (lattice) vibrations. This spatially resolved spectroscopic data, when coupled with Monte Carlo simulations, will enable quantitative assessments of mesoscopic structural order differences in solid materials. Our studies will provide both short- and long-term benefits for applied research in fields such as geoscience and archaeology. For example, our benchmark test materials (calcite and silica) will aid scientists who investigate how the crystallinity of carbonate and silicate minerals affects their abilities to sequester carbon dioxide. Differences in structural disorder of these minerals can also aid archaeological scientists who want to differentiate between geogenic and anthropogenic material formation pathways. The temporal and spatial evolution from amorphous to crystalline structures in magnesium calcites is a focal point for many in the field of biomineralization. Thus, this proposed instrument will enable a new research direction that is likely to have impact and importance to a broad scientific community.