Center for Functional Nanomaterials Seminar

The XX century opened new possibilities for the science by developing instrumentation. One example for this is the Scanning Tunneling Microscope, a technique which has played a significant role for our understanding the processes at the atomic scale. In recent years it has been shown that STM and other techniques can be used for investigation or adsorption and self-assembly of organic compounds at the nano scale and from this investigations we can extract important information about the physical interactions, chemistry or biology that control this processes with implication for organo-metalic compounds.
Organo-metalic compounds contains in the structure bonding between carbon and metal or compounds containing metal element bonds with covalent character. In many cases coordination bonds between metal and organic ligand. Organic ligands are very often coordination through heteroatom as for example nitrogen or oxygen. In nature there are a lot of examples of coordination metal organic compounds, for example in hemoglobin iron center is coordinated through nitrogen atom from the aromatic ring, the other example is chlorophyll coordinated from magnesium atom from the chlorine ring. The main property of the metal-carbon coordination bonding is among covalent and ionic character, stable in solutions and reactively ionic for undergoing reactions.
In this talk would be shown the organization of organic molecules at metallic substrates with different reactivity. The purpose of the thesis is to conduct experiments where the metal-organic bonding plays a major role.
First will show experiments with porphyrin molecule, large organic macrocycle molecule which in its structure contains a Zn atom. This atom will be shown to be significant for the metal-organic bonding of neighbouring molecules through oxygen. The techniques which will be used are Scanning Tunneling Microscopy (STM) and X ray Photoemission Spectroscopy (XPS).