Angstrom-Resolved Interfacial Structure in Buried Organic-Inorganic Junctions
Craig P. Schwartz, Sumana L. Raj, Sasawat Jamnuch, Chris J. Hull, Paolo Miotti, Royce K. Lam, Dennis Nordlund, Can Berk Uzundal, C. D. Pemmaraju, Riccardo Mincigrucci, Laura Foglia, Alberto Simoncig, Marcello Coreno, C. Masciovecchio, L. Giannessi, Luca Poletto, Emiliano Principi, Michael Zuerch, Tod A. Pascal, Walter S. Drisdell, Richard J. Saykally
Abstract
Charge transport processes at interfaces play a crucial role in many processes. Here, the first soft x-ray second harmonic generation (SXR SHG) interfacial spectrum of a buried interface (boron-Parylene N) is reported. SXR SHG shows distinct spectral features that are not observed in x-ray absorption spectra, demonstrating its extraordinary interfacial sensitivity. Comparison to electronic structure calculations indicates a boron-organic separation distance of 1.9 Å, with changes of less than 1 Å resulting in easily detectable SXR SHG spectral shifts (ca. hundreds of milli-electron volts).