This research proposal focuses on the progress in the study of local interactions by Scanning Probe Methods (SPM). The here proposed plan is only possible due to our long-standing experience and equipment: Nanolino: Combined STM/AFM force microscopy in ultrahigh vacuum Nanolab: High resolution STM and XPS measurements in ultrahigh vacuum The following research topics will be addressed in this period: 1. High-resolution force microscopy and spectroscopy The electronic and mechanical properties of self-assembled metallic nanowires as well as molecular chains are investigated by combined tunneling and force microscopy. Evidence for bound states of Majorana fermions will be searched in Fe wires deposited on superconductive surfaces. It is expected that the zero bias peak of tunneling spectroscopy will show these bound states. High resolution force microscopy gives access to the atomic structures of the Fe chains and possibly provides further evidence of the bound states. On-surface chemistry will be used to assemble molecular chains or ribbons, which will be investigated by high resolution force microscopy, where the submolecuar structure is revealed by a CO-terminated probing tip. In addition, the molecular chains will be picked up by the metallic probing tip and moved across the surface to probe their mechanical properties. Quantitative data about adhesion and friction will be gained with the help of these well characterized mechanical junctions. Questions about the effect of commensurability of molecular wires in relation to the substrate will be addressed. A new strand of research is the combination of Kelvin force microscopy of single molecules with light exposure. We plan to investigate charge transfer mechanisms within single molecules as a function of wave length. 2. Electrons, atoms and molecules in porous on-surface networks: Properties in local and periodic confinement Novel phenomena and properties emerging from the cooperative interaction of electrons and adsorbates within confinements and in periodic arrays thereof are to be investigated. Scanning tunneling microscopy and spectroscopy shall be used for the high resolution mapping of the host-guest architectures and the electronic states. Complementary photon and photoelectron spectroscopies shall reveal the present chemical states and bonds. Well-established and new to be developed porous on-surface / sample architectures shall be investigated in their property to serve as hosting body for the atom-by-atom investigation of condensation and for their capability to form regular and irregular arrangements of quantum-boxes by interaction with the substrate electronic states. The atom-by-atom condensation experiments performed with one or more components like Ne, Xe, allow for unprecedented insight into condensation physics in comparison to numerical models. In collaboration with Nanolino also the forces acting involved in the formation of the confined condensates shall be investigated. The 2D quantum box arrays also provide a unique platform to investigate the coupling between nanometer confined quantum states by controlled patterning of these “quantum breadboards”.