Local probe investigation of molecular material

Abstract

Local probe methods have attractive possibilities for the investigation and modification of molecules. In the imaging mode, large interactions of the substrate and the local probe with the molecules can affect the quality of the results and generate artifacts. Two approaches have been selected to improve the quality of the local probe results: (i) a reduction of the interaction with signals that are less distance-dependent, such as third harmonic generation or damping of a lever oscillation; (ii) the measurement of all interactions which generate artifacts using instruments able to record several interactions simultaneously, such as tunnelling current, force and force gradient. By means of a deconvolution method that linearizes the complex distance-dependencies of the component forces around the working point, a deformation-free, soft organic film surface was reconstructed. © 1995.