In this project funded by the Experimental Physical Chemistry Program of the Chemistry Division, Maroncelli will study solvation, spectroscopy, and dynamics in supercritical fluids (SCF) and expanded-liquid mixtures. Computational and spectroscopic techniques will be used to obtain a molecular-level understanding of fluid environments near their critical points. Static and time-resolved electronic spectroscopy and molecular dynamics simulations will be applied to study solvation and its influence on excited-state charge-transfer reactions in prototypical dipolar, quadrupolar and nondipolar solvents. Time-resolved Stokes-shift experiments on solutes in supercritical fluids will probe local solute-solvent dynamics. Gas-expanded liquids will be studied as potential anti-solvents that may be capable of selective precipitation. Results of this project will impact not only research on supercritical fluids, but also more general areas such as the dynamics of regular liquids, dipolar and ion solvation, dielectric friction, optical line shapes, spectral shifts, and modelling of interaction potentials.
The molecular interactions within a liquid and those between solvent and solute molecules have been the object of numerous studies. Supercritical fluids are materials in a low density state that lacks the distinction between liquid and gaseous states. Currently SCFs are receiving considerable attention due to the possibility of interesting and technologically important applications in materials processing. However, our understanding of these complex systems is far from complete. The well balanced combination of experiments and simulation in this project will provide critical tests for models of solutes and solvents and helps train students in a growing field with both technological and fundamental relevance.
|Effective start/end date||2/15/03 → 1/31/06|
- National Science Foundation: $432,899.00