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Zenneck Group

Research Interests

 

1. Metal (precursor) complexes via metal evaporization

Metal evaporator with resistance heated tungsten spiral and Al2O3-crucible (top view) (image: Zenneck)

Metal evaporator with resistance heated tungsten spiral and Al2O3-crucible (top view) (image: Zenneck)

 

The metal evaporator in action (side view) (image: Zenneck)

The metal evaporator in action (side view) (image: Zenneck)

 

he metal evaporator (schematic and picturous representation): a) water cooled electrodes; b) to vacuum pump; c) to cooling trap; d) turnable metal capillary tube for product release; e) metal capillary tube for substrate inlet; f) rotating system; g) flange; h) metal evaporator; i) rotating flask (V=6l) (image: Zenneck)

The metal evaporator (schematic and picturous representation): a) water cooled electrodes; b) to vacuum pump; c) to cooling trap; d) turnable metal capillary tube for product release; e) metal capillary tube for substrate inlet; f) rotating system; g) flange; h) metal evaporator; i) rotating flask (V=6l) (image: Zenneck)

 

image: Zenneck

Image: Zenneck

 

Condensing metal vapors and unsaturated organic compounds including arenes and olefines simultaneously on a cooled wall generally forms very unstable organic substances. Therefore for instance 10 grams of iron can be evaporated within one hour and allowed to react with toluene at -100° C. Although the primary product disintegrates below -60° C, it easily reacts at this temperature forming intermediates which are very useful for a variety of stoichiometric and catalytic reactions. The preparation of metal dotated thermoplastics is also possible using this procedure.

2. Electrochemistry, Electron Paramagnetic Resonance

Intermediates offer redox reactions which result in products of short life. This kind of systems are suitable for electrochemical evidence. Convenient preparative conditions exist if – at room temperature – irreversible electron transfer reactions are obtained, which change to a reversible behaviour in the cold. These intermediates, which may be short-lived or stable only at lower temperatures, usually exhibit an odd number of electrons and so allow the use of EPR (Electron Paramagnetic Resonance). These products can also be obtained by in situ reduction on the surface of an electrode. Other applications of EPR in combination with electrochemical techniques are also used in various areas of chemistry.