Probing a Ruthenium Coordination Complex at the Ionic Liquid–Vacuum Interface with Reactive-Atom Scattering, X-ray Photoelectron Spectroscopy, and Time-of-Flight Secondary Ion Mass Spectrometry

The speciation, conformation, and reactivity of transition metal complexes at the gas-liquid interface is poorly understood, yet the potential is high for observing chemistry unique to this anisotropic interface and leveraging interfacial structure to control the state and environment of the complex. If transition metal complexes can be designed to populate a liquid-vacuum interface preferentially, then it may be possible explore catalytic behavior by delivering reactants to the interface with a molecular beam and monitoring the scattering dynamics of reaction products to obtain detailed information on the reaction mechanism. In this initial experimental study, we have used reactive-atom scattering (RAS) with a hyperthermal F-atom probe, as well as X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (TOF-SIMS), to explore the interfacial composition and structure of a ~2 mg/mL solution of [RuCl2(p-cymene)P(C8H17)3] in perdeuterated 1-ethyl-3-methylimidazolium bis(tri...