X-ray Spectroscopy of Thin Film Free-Base Corroles: A Combined Theoretical and Experimental Characterization
Sprache des Titels:
Corrole compounds attract increasing interest due to their potential to stabilize high-valent metal states. X-ray spectroscopy is a powerful tool for the investigation and development of functional interfaces. For corrolic species, however, the required reference data are missing. Here, we employ a multitechnique X-ray investigation of thin films of the prototypical free-base 5,10,15-tris(pentafluorophenyl)corrole (3H-TpFPC) grown on the Ag(111) surface under ultrahigh vacuum conditions. Ultrapure corrole multilayer samples are prepared and characterized by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. In parallel, the X-ray fingerprints are simulated using the continued-fraction approach within density functional theory (DFT) for extended, (quasi-)periodic molecular structures. An excellent agreement between experimental and theoretical spectra enables a thorough interpretation of the detailed spectral features and proves an accurate description of the free-base corrole electronic structure within the present DFT approach. The present study provides X-ray spectroscopic references for all relevant core-level regions and absorption edges of intact molecular species and, thus, represents an ideal starting point for the comprehensive understanding of the complex chemistry of corroles in the adsorbed state toward the development of related functional interfaces.