- O’Neal, Jordan T;
- Champenois, Elio G;
- Oberli, Solène;
- Obaid, Razib;
- Al-Haddad, Andre;
- Barnard, Jonathan;
- Berrah, Nora;
- Coffee, Ryan;
- Duris, Joseph;
- Galinis, Gediminas;
- Garratt, Douglas;
- Glownia, James M;
- Haxton, Daniel;
- Ho, Phay;
- Li, Siqi;
- Li, Xiang;
- MacArthur, James;
- Marangos, Jon P;
- Natan, Adi;
- Shivaram, Niranjan;
- Slaughter, Daniel S;
- Walter, Peter;
- Wandel, Scott;
- Young, Linda;
- Bostedt, Christoph;
- Bucksbaum, Philip H;
- Picón, Antonio;
- Marinelli, Agostino;
- Cryan, James P
Free-electron lasers provide a source of x-ray pulses short enough and intense enough to drive nonlinearities in molecular systems. Impulsive interactions driven by these x-ray pulses provide a way to create and probe valence electron motions with high temporal and spatial resolution. Observing these electronic motions is crucial to understand the role of electronic coherence in chemical processes. A simple nonlinear technique for probing electronic motion, impulsive stimulated x-ray Raman scattering (ISXRS), involves a single impulsive interaction to produce a coherent superposition of electronic states. We demonstrate electronic population transfer via ISXRS using broad bandwidth (5.5 eV full width at half maximum) attosecond x-ray pulses produced by the Linac Coherent Light Source. The impulsive excitation is resonantly enhanced by the oxygen 1s→2π^{*} resonance of nitric oxide (NO), and excited state neutral molecules are probed with a time-delayed UV laser pulse.