Atom-specific activation in CO oxidation

• Published in: The Journal of chemical physics Vol. 149; no. 23; p. 234707
• Main Authors: Schreck, Simon, Diesen, Elias, LaRue, Jerry, Ogasawara, Hirohito, Marks, Kess, Nordlund, Dennis, Weston, Matthew, Beye, Martin, Cavalca, Filippo, Perakis, Fivos, Sellberg, Jonas, Eilert, André, Kim, Kyung Hwan, Coslovich, Giacomo, Coffee, Ryan, Krzywinski, Jacek, Reid, Alex, Moeller, Stefan, Lutman, Alberto, Öström, Henrik, Pettersson, Lars G M, Nilsson, Anders
• Format: Journal Article
• Language: English
• Published: United States 21.12.2018
• ISSN: 1089-7690
• DOI: 10.1063/1.5044579

We report on atom-specific activation of CO oxidation on Ru(0001) via resonant X-ray excitation. We show that resonant 1 core-level excitation of atomically adsorbed oxygen in the co-adsorbed phase of CO and oxygen directly drives CO oxidation. We separate this direct resonant channel from indirectly driven oxidation via X-ray induced substrate heating. Based on density functional theory calculations, we identify the valence-excited state created by the Auger decay as the driving electronic state for direct CO oxidation. We utilized the fresh-slice multi-pulse mode at the Linac Coherent Light Source that provided time-overlapped and 30 fs delayed pairs of soft X-ray pulses and discuss the prospects of femtosecond X-ray pump X-ray spectroscopy probe, as well as X-ray two-pulse correlation measurements for fundamental investigations of chemical reactions via selective X-ray excitation.