Coexistence of ketenimine species and tetra-σ adduct at acetyl cyanide/Si(1 0 0)-2 × 1

Abstract

The covalent binding of acetyl cyanide on Si(1 0 0)-2 × 1 has been investigated using high-resolution electron energy loss spectroscopy, X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations. The absence of the C O and C N stretching modes in the EELS spectra for chemisorbed molecules indicates the direct interactions between carbonyl, cyano groups and the dangling bonds on Si(1 0 0)-2 × 1. The characteristic C C N asymmetric stretching mode at 2031 cm −1 and C N stretching mode at 1667 cm −1 suggest the existence of both ketenimine species and tetra-σ adduct at the interface, further supported by XPS results and DFT calculations.