Grad School Research, Explained
I spent 6 years of grad school learning all sorts of tools, languages, and ways of thinking to call myself a computational scientist. Part of that journey has included learning how to explain the science projects I've worked on to people who run the other way when hearing words like "ab initio molecular dynamics," "pseudopotential," or "Fourier transform." Hopefully I've done an acceptable job below.
Interacting Nanoparticles at Finite Temperature
Films of small particles called nanoparticles are promising materials to replace silicon in solar cells, due to their highly tunable properties based on size, shape, and composition. When experimental scientists build solar cells using these materials, the nanoparticles form a grid-like layer, where each nanoparticle interacts with its neighbors and any deviations from a perfect grid (caused by temperature changes, limitations in synthesis, etc) lower the efficiency of the solar cell. Despite the unavoidable nanoparticle interactions and temperature effects observed in the lab, when computational scientists simulate these systems, interactions and temperature are nearly always ignored because it's cheaper and easier to do so. In this project, I explored the influence of interactions between nanoparticles at high temperature conditions, and showed how the properties of nanoparticles can differ depending on the way they interact. I discovered that the interacting nanoparticles behave as little "antennas" with fluctuating electronic properties that can explain discrepancies throughout literature.
You can read the full article here and watch above to see how two different nanoparticle systems interact!
Electron Interactions in Metal-Organic Frameworks
Metal-Organic Frameworks (MOFs) are porous materials that are ideal for storage, purification, and separation of gases such as hydrogen because the "holes" in the materials can be filled by other compounds (such as those gases). The interactions between the metal ion centers and the insulating "linkers" between them has been of particular interest, and there has been a desire to find porous materials that behave "ferromagnetically" (like a refrigerator magnet) or "antiferromagnetically" (zero total magnetism due to perfect cancellation between neighboring electrons). In this collaboration with experimental chemists, we found a unique combination of materials to synthesize and characterize a new series of MOFs. My calculations confirmed the antiferromagnetic behavior of these materials and explained why other electron configurations were unfavorable.
You can read the full article here. Sorry, no video for this one!
Strain and Confinement in Nanoplatelets
Nanoplatelets are two-dimensional, atomically-precise materials that are the perfect platform for computational studies, since their structures are so well known. In addition to simple, single-material nanoplatelets, one can synthesize complex layered (or "sandwich") platelets, where the material composition can change at each layer. For these systems, the interface between materials is unknown, and understanding the interplay between strain at the surfaces and confinement due to the size of the platelets would allow us to come up with "design rules" to tailor these materials to suit different applications. In collaboration with experimental chemists, I have been disentangling these two effects using simulations and analytical modelling.
This project is still in progress - stay tuned for links to articles and more information!