Supramolecular engineering of guanine-based self-assembled architectures at surfaces and interfaces
a) Chemical structure of guanine (G). Examples of H-bonded motifs of guanines : b) G4 (involving pairing : N(2)-H…N(7) and N(1)-H…O(6)), and c) ribbon-like (involving pairing : N(2)-H…O(6) and N(1)-H…N(7)).
The self-assembly of small organic molecules interacting via non-covalent forces is a viable approach towards the generation of highly ordered nanostructured materials.
Among various molecular building blocks, supramolecular architectures with specific motifs can be obtained trough self-association of natural nucleobases on flat surfaces. Such structures can be used as scaffolds to position electrically/optically active units in pre-determined locations in 2D, thereby paving the way towards materials suitable for a wide range of applications, e.g. in electronic, spintronics and optical devices.
In this mini-review, we discuss the supramolecular engineering of guanine derivatives and their self-assembly processes on conductive solid substrates, as investigated by scanning tunnelling microscopy (STM).