کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5424321 | 1395819 | 2009 | 9 صفحه PDF | دانلود رایگان |
In this article we report our findings on the electronic structure of the Li induced Ge(1 1 1)-3 Ã 1 reconstruction as determined by angle-resolved ultraviolet photoelectron spectroscopy (ARUPS) and core-level spectroscopy using synchrotron radiation. The results are compared to the theoretical honeycomb-chain-channel (HCC) model for the 3 Ã 1 reconstruction as calculated using density functional theory (DFT). ARUPS measurements were performed in both the ί-M¯ and ί-K¯ directions of the 1 Ã 1 surface Brillouin zone at photon energies of 17 and 21.2 eV. Three surface related states were observed in the ί-K¯ direction. In the ί-M¯ direction, at least two surface states were seen. The calculated band structure using the single-domain HCC model for Li/Ge(1 1 1)-3 Ã 1 was in good agreement with experiment, allowing for the determination of the origin of the experimentally observed surface states. In the Ge 3d core-level spectra, two surface related components were identified, both at lower binding energy with respect to the Ge 3d bulk peak. Our DFT calculations of the surface core-level shifts were found to be in fair agreement with the experimental results. Finally, in contrast to the Li/Si(1 1 1)-3 Ã 1 case, no double bond between Ge atoms in the top layer was found.
Journal: Surface Science - Volume 603, Issue 4, 15 February 2009, Pages 727-735