title: Covalent and reversible short-range electrostatic imaging in noncontact atomic force microscopy.
abstract: We present a computational study of atomic-scale image formation in noncontact atomic force microscopy on metallic surfaces. We find two imaging scenarios: (1). atomic resolution arising due to very strong covalent tip-sample interaction exhibiting striking similarity with the imaging mechanism found on semiconductor surfaces, and (2). a completely new mechanism, reversible short-range electrostatic imaging, arising due to subtle charge-transfer interactions. Contrary to the strong covalent-bond imaging, the newly identified mechanism causes only negligible surface perturbation and can account for results recently observed experimentally.
authors.affiliation: Center for Computational Materials Science (CCMS), Slovak University of Technology (FEI STU), Ilkovicova 3, SK-812 19, Bratislava, Slovakia.
authors.forename: Peter
authors.initials: P
authors.lastname: Dieska
authors.forename: Ivan
authors.initials: I
authors.lastname: Stich
authors.forename: Rubén
authors.initials: R
authors.lastname: Pérez