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The adsorption of heptahelicene, a helically shaped polyaromatic hydrocarbon (C(30)H(18)), on a Cu(111) surface was studied by means of thermal desorption mass spectrometry (TDMS) and low energy electron diffraction (LEED) at temperatures between 130-1,000 K under ultrahigh vacuum (UHV) conditions. The molecule in the monolayer remains intact up to 400 K. Above that temperature it decomposes in several steps into carbon and hydrogen, desorbing subsequently as H(2). In the saturated monolayer of the racemate the enantiomers are separated into two different domains on the surface which are mirror images of each other. After adsorption of one enantiomer only, no mirror domains were observed.

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Near-edge X-ray absorption spectroscopy with linearly polarized synchrotron radiation has been applied to study the orientation of the helically shaped polyaromatic hydrocarbon P-heptahelicene (C 30 H 12 ) on a Ni(100) surface under ultrahigh vacuum (UHV) conditions. By measuring the polarization dependence of the C1s f π* transitions the local adsorption geometry was determined. Between the helical axis of the molecule and the surface plane an angle of 43 ( 5°was observed for a saturated monolayer.

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Chiral organic surfaces were generated via adsorption of the pure enantiomers of heptahelicene, a helically shaped aromatic hydrocarbon, on a Ni(111) surface in ultra high vacuum. Time-of-flight secondary mass spectrometry (ToF-SIMS) revealed that the molecule stays intact at room temperature. The formation of a two-dimensionally ordered structure at monolayer coverage is observed via low-energy electron diffraction (LEED) and scanning tunnelling spectroscopy (STM). For creation of a chiral metal film, the chiral organic monolayer was subjected to subsequent metal physical vapour deposition. Differences in morphology of grown copper and palladium films were only observed when heptahelicene was adsorbed prior to deposition. No screw dislocations with preferred handedness were observed when the pure enantiomers were used.

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