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dc.contributor.authorMönig, H.en_US
dc.contributor.authorTodorović, M.en_US
dc.contributor.authorBaykara, M. Z.en_US
dc.contributor.authorSchwendemann, T. C.en_US
dc.contributor.authorRodrigo, L.en_US
dc.contributor.authorAltman, E. I.en_US
dc.contributor.authorPérez, R.en_US
dc.contributor.authorSchwarz, U. D.en_US
dc.date.accessioned2016-02-08T09:33:40Z
dc.date.available2016-02-08T09:33:40Z
dc.date.issued2013en_US
dc.identifier.issn1936-0851
dc.identifier.urihttp://hdl.handle.net/11693/20710
dc.description.abstractA comprehensive analysis of contrast formation mechanisms in scanning tunneling microscopy (STM) experiments on a metal oxide surface is presented with the oxygen-induced (2√2×√2)R45 missing row reconstruction of the Cu(100) surface as a model system. Density functional theory and electronic transport calculations were combined to simulate the STM imaging behavior of pure and oxygen-contaminated metal tips with structurally and chemically different apexes while systematically varying bias voltage and tip-sample distance. The resulting multiparameter database of computed images was used to conduct an extensive comparison with experimental data. Excellent agreement was attained for a large number of cases, suggesting that the assumed model tips reproduce most of the commonly encountered contrast-determining effects. Specifically, we find that depending on the bias voltage polarity, copper-terminated tips allow selective imaging of two structurally distinct surface Cu sites, while oxygen-terminated tips show complex contrasts with pronounced asymmetry and tip-sample distance dependence. Considering the structural and chemical stability of the tips reveals that the copper-terminated apexes tend to react with surface oxygen at small tip-sample distances. In contrast, oxygen-terminated tips are considerably more stable, allowing exclusive surface oxygen imaging at small tip-sample distances. Our results provide a conclusive understanding of fundamental STM imaging mechanisms, thereby providing guidelines for experimentalists to achieve chemically selective imaging by properly selecting imaging parameters. © 2013 American Chemical Society.en_US
dc.language.isoEnglishen_US
dc.source.titleACS Nanoen_US
dc.relation.isversionofhttp://dx.doi.org/10.1021/nn4045358en_US
dc.subjectSTM contrasten_US
dc.subjectDFT simulationen_US
dc.subjectMetal oxideen_US
dc.subjectTip asymmetryen_US
dc.subjectTip chemistryen_US
dc.subjectTip oxidationen_US
dc.titleUnderstanding scanning tunneling microscopy contrast mechanisms on metal oxides: a case studyen_US
dc.typeArticleen_US
dc.departmentDepartment of Mechanical Engineeringen_US
dc.departmentInstitute of Materials Science and Nanotechnology (UNAM)en_US
dc.citation.spage10233en_US
dc.citation.epage10244en_US
dc.citation.volumeNumber7en_US
dc.citation.issueNumber11en_US
dc.identifier.doi10.1021/nn4045358en_US
dc.publisherAmerican Chemical Societyen_US


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