Time-Resolved X-ray Photoelectron Spectroscopy: Ultrafast Dynamics in CS<sub>2</sub>Probed at the S 2p Edge
Ian Gabalski, Felix Allum, Issaka Seidu, Mathew Britton, Günter Brenner, H. Bromberger, M. Brouard, P. H. Bucksbaum, Michael Burt, James Cryan, Taran Driver, Nagitha Ekanayake, Benjamin Erk, Diksha Garg, Eva Gougoula, David Heathcote, Paul Hockett, D.M.P. Holland, Andrew J. Howard, Sonu Kumar, Jason W. L. Lee, Siqi Li, Joseph McManus, Jochen Mikosch, Dennis Milešević, Russell S. Minns, Simon P. Neville, A. Atia-Tul-Noor, Christina C. Papadopoulou, Christopher Passow, Weronika O. Razmus, Anja Röder, Arnaud Rouzée, Alcides Simão, James Unwin, Claire Vallance, Tiffany Walmsley, Jun Wang, Daniel Rolles, Albert Stolow, Michael S. Schuurman, Ruaridh Forbes
Abstract
High Resolution Image Download MS PowerPoint Slide Recent developments in X-ray free-electron lasers have enabled a novel site-selective probe of coupled nuclear and electronic dynamics in photoexcited molecules, time-resolved X-ray photoelectron spectroscopy (TRXPS). We present results from a joint experimental and theoretical TRXPS study of the well-characterized ultraviolet photodissociation of CS 2, a prototypical system for understanding non-adiabatic dynamics. These results demonstrate that the sulfur 2p binding energy is sensitive to changes in the nuclear structure following photoexcitation, which ultimately leads to dissociation into CS and S photoproducts. We are able to assign the main X-ray spectroscopic features to the CS and S products via comparison to a first-principles determination of the TRXPS based on ab initio multiple-spawning simulations. Our results demonstrate the use of TRXPS as a local probe of complex ultrafast photodissociation dynamics involving multimodal vibrational coupling, nonradiative transitions between electronic states, and multiple final product channels.