Research Fellows Directory
Dr Russell Minns
University of Southampton
Chemical reactions occur very quickly and involve motions on the scale of molecular bonds (10-10 m). This means many chemical reactions are complete within a few millionths of a billionth of a second. Measuring these changes is therefore technically challenging and explains why until recently it has been impossible. A number of techniques can now make measurements on these time and length scales, however, technological limitation have meant that only small portions of the full reaction path can be experimentally measured. In our research group we take advantage of recent advances in laser technology that now allow us to produce ultrashort, high intensity and high energy pulses of light that can remove this limited observation window, allowing us to measure all of the critical points in a photochemical reaction for the first time. The pulses have a duration of approximately 0.000000000000001 seconds which we can use as a chemical camera to take snapshots of chemical reactions as they happen. The experiments use a first laser pulse to initiate a reaction sending a molecule from reactants to products. A second, time-delayed laser pulse is used as a probe and gives information on the reaction dynamics. In our lab we study the fundamental mechanisms through which light energy is absorbed and redistributed around a molecule. The energy can cause the molecule to start moving, change shape or even fall apart, processes that drive all photochemical reactivity in both natural and man-made systems. By understanding the basic steps at the heart of these processes we look to understand the machinery behind biologically (photosynthesis) and industrially important (solar energy capture) light driven processes.
Interests and expertise (Subject groups)