Grant: Discovery Grants Program - Individual

Ongoing advances in synthesis and experimental characterization techniques yield detailed molecular-level information about chemical processes that is becoming increasingly difficult to decipher without the guidance of modeling. Computer simulations have thus permeated all branches of chemistry as they help interpret convoluted experimental data and inform experimental design. Our research centers on the development and application of state-of-the-art molecular dynamics and quantum chemistry techniques for realistic simulations of molecular interactions, structural properties and chemical processes, enabled by high-performance computing, accelerated by machine learning and validated against top-notch experiments. Connection with experiment is crucial to assess the reliability of our theoretical models, which can in turn be used to improve our fundamental understanding of chemistry.      The proposed research program involves new directions for realistic computer simulations, which include an improved description of the molecular interactions (from first-principles high-level quantum chemistry or approximate density-functional theory), quantum nuclear and possible nonadiabatic effects in dynamical simulations, as well as multiscale modeling to reach time and length scales appropriate for practical engineering applications. This array of theoretical tools will allow us (and others) to simulate particularly challenging chemical and biochemical problems and systems. Among those are nanoscale assemblies of various ionic and polar compounds such as inorganic ions and salts, organics and phospholipids in mixed solvent clusters and droplets, as well as bulk solvation phenomena for proteins and salts in complex (mixed-solvent) environments. Specific core foci include 1) the structure and thermodynamics of seeded water droplets, 2) the photochemistry of ionic clusters to probe solvation structure and dynamics, 3) the stability of biomolecules in mixed (solvent-osmolyte) environments and upon encapsulation, and 4) the structural and chemical properties of highly concentrated (electrolyte) salt solutions.      Beyond establishing advanced modeling and simulation methodologies and unveiling physical chemistry fundamentals of complex solvation processes, this research will be driven by applications in environmental sciences (chemistry of organic molecules/pollutants in aerosols or soil particles, their fate upon light irradiation in the atmosphere), biophysical chemistry (time-resolved chemistry of DNA radiation damage, protein denaturation), bioanalytical chemistry (selection of mobile-phase additives in lipidomics), biologics formulation (choice of encapsulation matrices to ensure the stability of biologically active molecules such as vaccines over long periods of time under ambient conditions) and electrochemistry (electrolyte engineering for advanced electrocatalytic production of fertilizers or all-solid-state batteries).