Résumé
We have recently developed an in-vacuum microjet setup adapted to our high energy photoemission HAXPES station located at the GALAXIES beamline at SOLEIL [1-2]. It allows studying the electronic structure of simple solutions by means of hard X-rays. The use of the high photon energy is a real advantage compared with other existing setups since the bulk of the liquid, and not only its interface with vacuum, can be probed. In addition, creating deep core holes on selected chemical elements triggers ultrafast dynamical processes occurring of (sub)-fs timescale that we can highlight by photoelectron and Auger spectroscopies. I will present part of the first experimental measurements we collected with this equipment in particular I will show our first results on KCl aqueous solution and on mixed CuCl2/glycine aqueous solutions. In the potassium chloride case, the Auger spectra show interesting features that we interpreted – thanks to theoretical support – to ultrafast electron transfer. Contrary to the one of chloride, the KLL Auger spectrum of potassium exhibits an obvious large extra structure that is described by configurations corresponding to delocalized states between water and potassium. These states originate from a charge migration from the solvent to the core-ionized potassium ion induced by the photoionization step and occurring during the K-shell core-hole lifetime. The very recent studies on copper aimed at determining how the bonding of glycine with the metallic dication and how its concentration modify the Cu2p XPS spectra. I will briefly discuss these results by comparing them with the known CuO case.
[1] J.-P. Rueff et al, Journal of Synchrotron Radiation 22, (2015) 175
[2] D. Céolin et al., Journal of Electron Spectroscopy and Related Phenomena 190, (2013) 188
