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Title: Quantitative LEED I-V and ab initio study of the Si(111)-3x2-Sm surface structure and the missing half-order spots in the 3x1 diffraction pattern

Abstract

We have used low-energy electron diffraction (LEED) I-V analysis and ab initio calculations to quantitatively determine the honeycomb chain model structure for the Si(111)-3x2-Sm surface. This structure and a similar 3x1 recontruction have been observed for many alkali-earth and rare-earth metals on the Si(111) surface. Our ab initio calculations show that there are two almost degenerate sites for the Sm atom in the unit cell, and the LEED I-V analysis reveals that an admixture of the two in a ratio that slightly favors the site with the lower energy is the best match to experiment. We show that the I-V curves are insensitive to the presence of the Sm atom and that this results in a very low intensity for the half-order spots, which might explain the appearance of a 3x1 LEED pattern produced by all of the structures with a 3x2 unit cell.

Authors:
; ;  [1]
  1. Department of Physics, University of York, York YO10 5DD (United Kingdom)
Publication Date:
OSTI Identifier:
21045882
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 20; Other Information: DOI: 10.1103/PhysRevB.75.205420; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ELECTRON DIFFRACTION; INTERFACES; SAMARIUM; SEMICONDUCTOR MATERIALS; SILICON; SURFACES

Citation Formats

Eames, C., Probert, M. I. J., and Tear, S. P. Quantitative LEED I-V and ab initio study of the Si(111)-3x2-Sm surface structure and the missing half-order spots in the 3x1 diffraction pattern. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.205420.
Eames, C., Probert, M. I. J., & Tear, S. P. Quantitative LEED I-V and ab initio study of the Si(111)-3x2-Sm surface structure and the missing half-order spots in the 3x1 diffraction pattern. United States. doi:10.1103/PHYSREVB.75.205420.
Eames, C., Probert, M. I. J., and Tear, S. P. Tue . "Quantitative LEED I-V and ab initio study of the Si(111)-3x2-Sm surface structure and the missing half-order spots in the 3x1 diffraction pattern". United States. doi:10.1103/PHYSREVB.75.205420.
@article{osti_21045882,
title = {Quantitative LEED I-V and ab initio study of the Si(111)-3x2-Sm surface structure and the missing half-order spots in the 3x1 diffraction pattern},
author = {Eames, C. and Probert, M. I. J. and Tear, S. P.},
abstractNote = {We have used low-energy electron diffraction (LEED) I-V analysis and ab initio calculations to quantitatively determine the honeycomb chain model structure for the Si(111)-3x2-Sm surface. This structure and a similar 3x1 recontruction have been observed for many alkali-earth and rare-earth metals on the Si(111) surface. Our ab initio calculations show that there are two almost degenerate sites for the Sm atom in the unit cell, and the LEED I-V analysis reveals that an admixture of the two in a ratio that slightly favors the site with the lower energy is the best match to experiment. We show that the I-V curves are insensitive to the presence of the Sm atom and that this results in a very low intensity for the half-order spots, which might explain the appearance of a 3x1 LEED pattern produced by all of the structures with a 3x2 unit cell.},
doi = {10.1103/PHYSREVB.75.205420},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 20,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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