skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Theoretical studies of positron states and annihilation characteristics at the oxidized Cu(100) surface

Abstract

In this work we present the results of theoretical studies of positron surface and bulk states and annihilation probabilities of surface-trapped positrons with relevant core electrons at the oxidized Cu(100) surface under conditions of high oxygen coverage. An ab-initio study of the electronic properties of the Cu(100) missing row reconstructed surface at various on surface and sub-surface oxygen coverages has been performed on the basis of the density functional theory (DFT) using the Dmol3 code and the generalized gradient approximation (GGA). Surface structures in calculations have been constructed by adding oxygen atoms to various surface hollow and sub-surface octahedral sites of the 0.5 monolayer (ML) missing row reconstructed phase of the Cu(100) surface with oxygen coverages ranging from 0.5 to 1.5 ML. The charge redistribution at the surface and variations in atomic structure and chemical composition of the topmost layers associated with oxidation and surface reconstruction have been found to affect the spatial extent and localization of the positron surface state wave function and annihilation probabilities of surface trapped positrons with relevant core electrons. Theoretical results are compared with experimental data obtained from studies of oxidation of the Cu(100) surface using positron annihilation induced Auger electron spectroscopy (PAES). It hasmore » been shown that positron annihilation probabilities with Cu 3s and 3p core electrons decrease when total (on-surface and sub-surface) oxygen coverage of the Cu(100) surface increases up to 1 ML. The calculations show that for high oxygen coverage when total oxygen coverage is 1. 5 ML the positron is not bound to the surface.« less

Authors:
 [1];  [2]
  1. Department of Physics, Box 19059, University of Texas at Arlington, Arlington Texas 76019 (United States) and Institute of Physics, Kazan Federal University, Kremlevskaya18, Kazan 420008 (Russian Federation)
  2. Department of Physics, Box 19059, University of Texas at Arlington, Arlington Texas 76019 (United States)
Publication Date:
OSTI Identifier:
22116993
Resource Type:
Journal Article
Journal Name:
AIP Conference Proceedings
Additional Journal Information:
Journal Volume: 1525; Journal Issue: 1; Conference: 22. international conference on application of accelerators in research and industry, Ft. Worth, TX (United States), 5-10 Aug 2012; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0094-243X
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ANNIHILATION; APPROXIMATIONS; AUGER ELECTRON SPECTROSCOPY; CHEMICAL COMPOSITION; COMPARATIVE EVALUATIONS; COPPER; DENSITY FUNCTIONAL METHOD; ELECTRONS; LAYERS; OXIDATION; OXYGEN; POSITRONS; PROBABILITY; SURFACES; TRAPPING; WAVE FUNCTIONS

Citation Formats

Fazleev, N. G., and Weiss, A. H. Theoretical studies of positron states and annihilation characteristics at the oxidized Cu(100) surface. United States: N. p., 2013. Web. doi:10.1063/1.4802372.
Fazleev, N. G., & Weiss, A. H. Theoretical studies of positron states and annihilation characteristics at the oxidized Cu(100) surface. United States. https://doi.org/10.1063/1.4802372
Fazleev, N. G., and Weiss, A. H. 2013. "Theoretical studies of positron states and annihilation characteristics at the oxidized Cu(100) surface". United States. https://doi.org/10.1063/1.4802372.
@article{osti_22116993,
title = {Theoretical studies of positron states and annihilation characteristics at the oxidized Cu(100) surface},
author = {Fazleev, N. G. and Weiss, A. H.},
abstractNote = {In this work we present the results of theoretical studies of positron surface and bulk states and annihilation probabilities of surface-trapped positrons with relevant core electrons at the oxidized Cu(100) surface under conditions of high oxygen coverage. An ab-initio study of the electronic properties of the Cu(100) missing row reconstructed surface at various on surface and sub-surface oxygen coverages has been performed on the basis of the density functional theory (DFT) using the Dmol3 code and the generalized gradient approximation (GGA). Surface structures in calculations have been constructed by adding oxygen atoms to various surface hollow and sub-surface octahedral sites of the 0.5 monolayer (ML) missing row reconstructed phase of the Cu(100) surface with oxygen coverages ranging from 0.5 to 1.5 ML. The charge redistribution at the surface and variations in atomic structure and chemical composition of the topmost layers associated with oxidation and surface reconstruction have been found to affect the spatial extent and localization of the positron surface state wave function and annihilation probabilities of surface trapped positrons with relevant core electrons. Theoretical results are compared with experimental data obtained from studies of oxidation of the Cu(100) surface using positron annihilation induced Auger electron spectroscopy (PAES). It has been shown that positron annihilation probabilities with Cu 3s and 3p core electrons decrease when total (on-surface and sub-surface) oxygen coverage of the Cu(100) surface increases up to 1 ML. The calculations show that for high oxygen coverage when total oxygen coverage is 1. 5 ML the positron is not bound to the surface.},
doi = {10.1063/1.4802372},
url = {https://www.osti.gov/biblio/22116993}, journal = {AIP Conference Proceedings},
issn = {0094-243X},
number = 1,
volume = 1525,
place = {United States},
year = {Fri Apr 19 00:00:00 EDT 2013},
month = {Fri Apr 19 00:00:00 EDT 2013}
}