Investigation of Unoccupied Electronic States near the Fermi Level of Polysilane using Resonant Auger Spectroscopy

Abstract

Unoccupied electronic states near the Fermi level of poly(dimethylsilane) were probed using Si 1s X-ray absorption spectroscopy (XAS) and Si KL_2,3L_2,3 resonant Auger spectroscopy (RAS). The measured resonance peaks of XAS spectra near Si K-edge have been assigned in comparison with the discrete variational (DV)-Xα molecular orbital calculations. The rapid delocalization of Si 1s core-excited electron through the empty conduction band was observed along the polymer chain with the energy-dependent RAS measurement, and the electron delocalization time was estimated based on the core-hole clock method.

Keywords:

• X-ray absorption spectroscopy; resonant Auger spectroscopy
• polysilane
• σ-conjugated polymer
• core hole clock

Acknowledgments

We thank the staff of the Photon Factory and BL-27A (JAEA) for supporting experiments. This work was performed under the approval of the Photon Factory Program Advisory Committee (Proposal No. 2010G653 and 2013G714).