title: Interplay between Steps and Oxygen Vacancies on Curved TiO2(110).
abstract: A vicinal rutile TiO2(110) crystal with a smooth variation of atomic steps parallel to the [1-10] direction was analyzed locally with STM and ARPES. The step edge morphology changes across the samples, from [1-11] zigzag faceting to straight [1-10] steps. A step-bunching phase is attributed to an optimal (110) terrace width, where all bridge-bonded O atom vacancies (Obr vacs) vanish. The [1-10] steps terminate with a pair of 2-fold coordinated O atoms, which give rise to bright, triangular protrusions (St) in STM. The intensity of the Ti 3d-derived gap state correlates with the sum of Obr vacs plus St protrusions at steps, suggesting that both Obr vacs and steps contribute a similar effective charge to sample doping. The binding energy of the gap state shifts when going from the flat (110) surface toward densely stepped planes, pointing to differences in the Ti(3+) polaron near steps and at terraces.
authors.affiliation: Centro de Física de Materiales (CSIC-UPV/EHU) , Manuel Lardizabal 5, 20018 San Sebastián, Spain.|Donostia International Physics Center (DIPC) , 20018 San Sebastián, Spain.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Miccio
authors.affiliation: Institute of Applied Physics, Vienna University of Technology , Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Setvin
authors.affiliation: CIC nanoGUNE , Avenido Tolosa 76, 20018 San Sebastián, Spain.
authors.forename: Moritz
authors.initials: M
authors.lastname: Müller
authors.affiliation: Centro de Física de Materiales (CSIC-UPV/EHU) , Manuel Lardizabal 5, 20018 San Sebastián, Spain.
authors.forename: Mikel
authors.initials: M
authors.lastname: Abadía
authors.affiliation: Centro de Física de Materiales (CSIC-UPV/EHU) , Manuel Lardizabal 5, 20018 San Sebastián, Spain.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Piquero
authors.affiliation: Centro de Física de Materiales (CSIC-UPV/EHU) , Manuel Lardizabal 5, 20018 San Sebastián, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Lobo-Checa
authors.affiliation: Centro de Física de Materiales (CSIC-UPV/EHU) , Manuel Lardizabal 5, 20018 San Sebastián, Spain.|Fachbereich Physik und Zentrum für Materialwissenschaften, Philipps-Universität Marburg , 35032 Marburg, Germany.
authors.forename: Frederik
authors.initials: F
authors.lastname: Schiller
authors.affiliation: Centro de Física de Materiales (CSIC-UPV/EHU) , Manuel Lardizabal 5, 20018 San Sebastián, Spain.
authors.forename: Celia
authors.initials: C
authors.lastname: Rogero
authors.affiliation: Institute of Applied Physics, Vienna University of Technology , Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Schmid
authors.affiliation: Centro de Física de Materiales (CSIC-UPV/EHU) , Manuel Lardizabal 5, 20018 San Sebastián, Spain.|Donostia International Physics Center (DIPC) , 20018 San Sebastián, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Sánchez-Portal
authors.affiliation: Institute of Applied Physics, Vienna University of Technology , Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Diebold
authors.affiliation: Centro de Física de Materiales (CSIC-UPV/EHU) , Manuel Lardizabal 5, 20018 San Sebastián, Spain.|Donostia International Physics Center (DIPC) , 20018 San Sebastián, Spain.|Departamento de Física Aplicada, Universidad del País Vasco (UPV/EHU) , 20080 San Sebastián, Spain.
authors.forename: J Enrique
authors.initials: JE
authors.lastname: Ortega
keywords: STM; Titanium oxide; curved crystal; oxygen vacancy; photoemission; rutile; vicinal surface