Spin-state studies with XES and RIXS: From static to ultrafast

• DOI: 10.1016/j.elspec.2012.09.012
• Publication Date: 2012-09-29T19:47:31Z
• Authors: György Vankó; Amélie Bordage; Pieter Glatzel; Erik Gallo; Mauro Rovezzi; Wojciech Gawelda; Andreas Galler; Christian Bressler; Gilles Doumy; Anne Marie March; Elliot P. Kanter; Linda Young; Stephen H. Southw...; Sophie E. Canton; Jens Uhlig; Grigory Smolentsev; Villy Sundström; Kristoffer Haldrup; Tim Brandt van Driel; Martin M. Nielsen; Kasper S. Kjaer; Henrik T. Lemke
• Keywords: Time-resolved spectroscopy; Photoinduced transition; Pump-probe experiments; X-ray spectroscopy; [CHIM]Chemical Sciences; Spin transition; 02 engineering and technology; Ultrafast phenomena; 0210 nano-technology; Molecular switching; info:eu-repo/classification/ddc/620

We report on extending hard X-ray emission spectroscopy (XES) along with resonant inelastic X-ray scattering (RIXS) to study ultrafast phenomena in a pump-probe scheme at MHz repetition rates. The investigated systems include low-spin (LS) Fe-II complex compounds, where optical pulses induce a spin-state transition to their (sub)nanosecond-lived high-spin (HS) state. Time-resolved XES clearly reflects the spin-state variations with very high signal-to-noise ratio, in agreement with HS-LS difference spectra measured at thermal spin crossover, and reference HS-LS systems in static experiments, next to multiplet calculations. The 1s2p RIXS, measured at the Fe Is pre-edge region, shows variations after laser excitation, which are consistent with the formation of the HS state. Our results demonstrate that X-ray spectroscopy experiments with overall rather weak signals, such as RIXS, can now be reliably exploited to study chemical and physical transformations on ultrafast time scales. (C) 2012 Elsevier B.V. All rights reserved. (Less)