Inverse Photoemission Spectroscopy of Coinage Metal Corroles: Comparison with Solution-Phase Electrochemistry.

A combined direct and inverse photoemission study of coinage metal corroles suggests that the latter technique, in favorable cases, can provide some additional information relative to electrochemical measurements. Thus, whereas inverse photoemission spectroscopy (IPES) provides relative electron affinities for electron addition to different unoccupied orbitals, electrochemical reduction potentials shed light on the energetics of electron additions. While all three coinage metal triphenylcorrole (TPC) complexes exhibit similar ionization potentials, they exhibit dramatically different inverse photoemission spectra.

On-Surface Synthesis of Unsaturated Hydrocarbon Chains through C-S Activation.

We use an on-surface synthesis approach to drive the homocoupling reaction of a simple dithiophenyl-functionalized precursor on Cu(111). The C-S activation reaction is initiated at low annealing temperature and yields unsaturated hydrocarbon chains interconnected in a fully conjugated reticulated network. High-resolution atomic force microscopy imaging reveals the opening of the thiophenyl rings and the presence of trans- and cis-oligoacetylene chains as well as pentalene units.

Unoccupied electronic states of 2D Si on Ag-3-Si(111).

Optimizing substrate characterization to grow 2D Si layers on surfaces is a major issue toward the development of synthesis techniques of the promising silicene. We have used inverse photoemission spectroscopy (IPES) to study the electronic band structure of an ordered 2D Si layer on the3×3-Ag/Si(111) surface (3-Ag). Exploiting the large upwards band bending of the3-Ag substrate, we could investigate the evolution of the unoccupied surface and interface states in most of the Si band gap.

Peculiar covalent bonding of C/6H-SiC(0 0 0 1)-(3 × 3) probed by photoelectron spectroscopy.

High resolution photoemission with synchrotron radiation was used to study the interface formation of a thin layer of C on 6H-SiC(0 0 0 1)-(3 × 3), characterized by protruding Si-tetramers. The results show that C is chemisorbed by orbital hybridization between the highest-occupied molecular orbital (HOMO) and the p orbital of Si adatom at the apex of the tetramers. The covalent nature of the bonding was inferred from core level as well as valence band spectra.