Baykara, M. Z.Mönig, H.Schwendemann, T. C.Ünverdi, Ö.Altman, E. I.Schwarz, U. D.2018-04-122018-04-1220160003-6951http://hdl.handle.net/11693/36660The extent to which point defects affect the local chemical reactivity and electronic properties of an oxide surface was evaluated with picometer resolution in all three spatial dimensions using simultaneous atomic force/scanning tunneling microscopy measurements performed on the (110) face of rutile TiO2. Oxygen atoms were imaged as protrusions in both data channels, corresponding to a rarely observed imaging mode for this prototypical metal oxide surface. Three-dimensional spectroscopy of interaction forces and tunneling currents was performed on individual surface and subsurface defects as a function of tip-sample distance. An interstitial defect assigned to a subsurface hydrogen atom is found to have a distinct effect on the local density of electronic states on the surface, but no detectable influence on the tip-sample interaction force. Meanwhile, spectroscopic data acquired on an oxygen vacancy highlight the role of the probe tip in chemical reactivity measurements.EnglishAtomsDefect densityElectron tunnelingElectronic propertiesMetalsOxide mineralsOxygen vacanciesPoint defectsTitanium dioxideInterstitial defectsLocal density of electronic statePicometer resolutionPrototypical metal oxide surfacesReactivity measurementsSubsurface hydrogensThree-dimensional interactionTip-sample interactionSurface defectsArticle10.1063/1.4942100