Coronenes, Crown ethers, Cryptands, Macrocycles, Squares, Rectangles

Coronenes, Crown ethers, Cryptands, Macrocycles, Squares, Rectangles 

Heckl and co-workers [140] incorporated coronene molecules into a molecular network of trimesic acid molecules. Some of the coronene molecules apparently rotated and single ones could be removed with an STM tip operated at the liquid-solid interface. The authors report that coronone molecules alone do not self-organize in heptanoic acid on graphite - the support of the trimesic acid molecule network is necessary. 

For the organization of coronene in heptanoic acid, the substrate material and/ or preparation procedure apparently matters Hipps and co-workers [141] investigated supramolecular assemblies of coronene with alkaline acids (hexanoic, heptanoic and octanoic) with STM also at the liquid-solid interface. While the dipole-dipole interactions produce bi-layers of one coronene molecule, which are surrounded by 12 acid molecules in the case of hexanoic and heptanoic acid, in octanoic acid, on the other hand, no solvent molecules are present in the coronene monolayer. 

Crown ethers Due to their inclusion capability, crown ether molecules are interesting hosts. Some detailed insights into the adsorption of crown ethers on surfaces as well as its inclusion of hosts have been already obtained in STM studies. 

Adlayers of metal free and preformed potassium complexes of dibenzo-lS-crown-6-ether molecules (organized on a Au(lll) surface under potential control) were in-situ imaged with STM [143]. The potassium ion appeared as ball shaped protrusion in the inclusion complex. 

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