Dr Jan R.R. Verlet
(email at j.r.r.verlet@durham.ac.uk)
Research Interests
With the advent of femtosecond lasers producing optical pulses of several femtoseconds (10-15 seconds), time-resolved spectroscopy is now able to probe events on such a timescale. As most molecular processes, such as a molecular vibration, occur on femto- to picosecond timescales, these may be observed directly and in real time. In general, a pump pulse optically initiates some event of interest, while a probe pulse monitors the change of the excited sample with time.
Our research focuses on the ultrafast dynamics of clusters, which are aggregates of a few to many thousands of atoms or molecules. Because the atoms or molecules are neither isolated or in a condensed phase, they may be thought of as forging a bridge between the two extremes. By investigating molecular processes with increasing cluster size, one can glean remarkable insights into the condensed phase processes. This is in part because a cluster provides a well-controlled and defined environment, large enough to capture bulk dynamics yet sufficiently small to attain high level of detail.
We are specifically interested in solvation dynamics and the chemical physics of complex anions such as multiply charged anions and biologically important species. In order to investigate solvation dynamics from a cluster perspective, we prepare an anion solvated by a known number of solvent molecules using mass-spectrometry. Because we may incrementally add individual solvent molecules, we can systematically probe perturbations induced by the solvent, thus building a molecular picture of how dynamical processes in anions alter from gas to condensed phase.
Recent Publications
"Electron solvation in water clusters following charge transfer from iodide", J.R.R. Verlet, A. Kammrath, G.B. Griffin and D.M. Neumark, J. Chem. Phys. 123, 231102 (2005)
"Observation of large water-cluster anions with surface-bound excess electrons", J.R.R. Verlet, A.E. Bragg, A. Kammrath, O. Cheshnovsky and D.M. Neumark,Science 307, 93 (2005)
"Electronic relxation dynamics in water cluster anions", A.E. Bragg, J.R.R. Verlet, A. Kammrath, O. Cheshnovsky and D.M. Neumark, J. Am. Chem. Soc 127, 15283 (2005)
"Hydrated electron dynamics: From clusters to bulk", A.E. Bragg, J.R.R. Verlet, A. Kammrath, O. Cheshnovsky and D.M. Neumark, Science 306, 669 (2004)