Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5423042 | Surface Science | 2012 | 5 Pages |
The electronic states of submonolayers and multilayers of cobalt(II) phthalocyanine (CoPc) adsorbed on Ag(111) were examined with photoelectron spectroscopy to obtain insight into the details of the substrate-adsorbate interaction. UV photoelectron spectroscopy (UPS) reveals the presence of two interaction-related valence states in the direct vicinity of the Fermi edge, in agreement with previous DFT calculations. X-ray photoelectron spectra indicate that the substrate-adsorbate interaction results in transfer of electron density from the substrate to the Co(II) ion. Substantial changes in the Co 2p multiplet structure, a spectral pattern induced by the open-shell character of the central Co(II) ion, indicate a complete quenching of the molecular spin. While pristine CoPc molecules are paramagnetic with SÂ =Â 1/2, molecules in direct contact to the Ag(111) substrate appear to be in a diamagnetic state.
Graphical abstractDownload high-res image (197KB)Download full-size imageHighlights⺠Co phthalocyanine on Ag(111) was studied with photoelectron spectroscopy (XPS/UPS). ⺠Co-Ag interaction evident from valence electronic structure and core level shifts. ⺠Adsorption-induced changes of Co 2p multiplet structure and spin-orbit splitting. ⺠Co 2p signal changes consistent with electron transfer from Ag substrate to Co ion.