2:15 PM - 2:30 PM
[22p-W631-5] Surface Chemistry of SnCl2Pc Thin Film on Ag(111): Absorption Configuration Observed by X-ray Standing Wave Technique
Keywords:X-ray standing wave,Organic Film,Phthalocyanine
The electronic structure of organic thin films on metal substrates is determined by their adsorption configuration. Therefore, understanding of such geometric properties of organic–metal interfaces is important for applications in the field of organic electronics. In this work we investigate the adsorption configuration of tinphthalocyanine dichloride (SnCl2Pc) on Ag(111) as a model system of an organic–metal interface using the X-ray standing wave (XSW) technique.
The experiments were performed at the Diamond Light Source, Beamline I09. A monolayer of SnCl2Pc was deposited on a Ag(111) surface The film thickness was confirmed by the comparison to our previous low energy electron diffraction (LEED) study. XSW was performed by measuring the photoemission intensities of core levels of each constituent atom (Sn3d, Cl2p, C1s, N1s) as a function of photon energy of the incident hard x-rays near Bragg reflection. All the measurements were done at room temperature.
Our XSW results suggest that one of the two Cl atoms of SnCl2Pc desorbs when the molecule adsorbs at room temperature. The remaining Cl atom is likely to be located ~0.2 Å deeper than the outermost Ag(111) layer. By heating the sample at ~480 K for 1 hour, the remaining Cl atom also desorbs, which was confirmed by the disappearance of the Cl2p core-level peaks in the x-ray photoemission spectra. Taking the dissociation temperature into account, it is unlikely that the Cl atom formed AgCl. The XSW results for N1s and C1s changed slightly after the sample heating, implying a change in the adsorption conformation due to detachment of the Cl atom.
A detailed adsorption configuration as well as the lattice structure measured by scanning tunneling microscopy and LEED will be reported. The electronic structure studied by photoemission spectroscopies will be elucidated in the following presentation.
The experiments were performed at the Diamond Light Source, Beamline I09. A monolayer of SnCl2Pc was deposited on a Ag(111) surface The film thickness was confirmed by the comparison to our previous low energy electron diffraction (LEED) study. XSW was performed by measuring the photoemission intensities of core levels of each constituent atom (Sn3d, Cl2p, C1s, N1s) as a function of photon energy of the incident hard x-rays near Bragg reflection. All the measurements were done at room temperature.
Our XSW results suggest that one of the two Cl atoms of SnCl2Pc desorbs when the molecule adsorbs at room temperature. The remaining Cl atom is likely to be located ~0.2 Å deeper than the outermost Ag(111) layer. By heating the sample at ~480 K for 1 hour, the remaining Cl atom also desorbs, which was confirmed by the disappearance of the Cl2p core-level peaks in the x-ray photoemission spectra. Taking the dissociation temperature into account, it is unlikely that the Cl atom formed AgCl. The XSW results for N1s and C1s changed slightly after the sample heating, implying a change in the adsorption conformation due to detachment of the Cl atom.
A detailed adsorption configuration as well as the lattice structure measured by scanning tunneling microscopy and LEED will be reported. The electronic structure studied by photoemission spectroscopies will be elucidated in the following presentation.