The interaction of organic molecules with a clean and reduced TiO2 surface

Adsorption and manipulation of organic molecules at inorganic surfaces has attracted much attention due to potential applications in molecular electronics. In particular, single porphyrinbased molecules deposited on copper substrates have recently been investigated and manipulated by means of their interaction with the STM tip [1]. Studying and manipulating similar and more complex organic molecules at oxide surfaces requires using Atomic Force Microscopy (AFM) and is even more challenging both experimentally and theoretically. The main problem for theory is the absence of reliable description of the interactions of relatively large organic molecules with oxide surfaces. The description of molecule/surface and molecule/surface/AFM tip systems on the ab initio level is hardly possible due to the size of these systems. Consequently, a more realistic description of the interactions in these systems should be achieved on an semi-empirical level, i.e. the force-fields for these systems should be derived.