Lawrence Ziegler

Professor Larry Ziegler is Chair of the Chemistry Department at Boston University. He and his group have received continued support from the NSF ($450K over 3 years) to use cutting edge spectroscopic techniques to advance understanding of supercritical fluids (SCFs) as a medium for chemical activity.

Using ultrafast vibrational or rotational spectroscopic techniques, he and his team of researchers study the femtosecond to picosecond solvation dynamics of a range of SCF solutions as a function of density for isotherms close to the critical temperature. The insights gained will identify those solvent motions coupled to the spectroscopically tagged solutes in the femtosecond to tens of picoseconds regime providing a dynamical description of solvation in the compressible fluid regime of SCFs. Such dynamics are important to understand, because they are intimately involved in the unique microscopic solvation phenomena that give super critical fluids their interesting and useful properties.

Given the very high relevance of supercritical liquids for applied chemistry on the one hand and the lack of detailed knowledge on their microscopic dynamics on the other, this research is expected to provide new and important insight into structural fluctuations and local interactions governing solvation processes and, thus, chemical dynamics.