Physics Colloquium: Eric Brauns, Department of Chemistry, University of Idaho

Monday, November 7 2011 at 4:00 PM

Location: EP 209

Physics Colloquium, presented by Eric Brauns, department of chemistry, University of Idaho, will occur Nov. 7 at 4 p.m. in EP 209. The title of his presentation is: Applications of time-resolved infrared spectroscopy: elementary processes in RNA folding and infrared photon migration in transparent and semi-transparent media

ABSTRACT: Braun will give an overview of the research that he does at the interface between chemistry and physics. In the first part of the talk, he'll discuss some of his work on the fast folding kinetics of small RNA loop structures. Rapidly heating the sample with a short laser pulse provides access to the fastest folding events. The conformational dynamics of the RNA subsequent to the "temperature jump" are monitored with time-resolved infrared (IR) spectroscopy. Despite the apparent structural simplicity of the RNA loop structures, his work shows that the folding mechanism is surprisingly complicated. He'll conclude the portion of the talk with a discussion of future work involving coherent 2D-IR spectroscopy. In the last part of the talk, he'll discuss work that he's been doing to study the ultrafast (picosecond and faster) migration of IR photons in transparent and semi-transparent media. His team's results show that prevailing theories to describe so-called "photon diffusion" break down on ultrafast time scales.