Self-assembly offers unique possibilities for creating ordered and functional surfaces. Using non-covalent interactions, researchers have constructed open networks that leave nanoscale areas of the surface uncovered. Alternatively, self-assembled monolayers offer a flexible route to tailoring the properties of an entire surface. Now, Rafael Madueno, Manfred Buck and colleagues at St Andrews University have combined these two approaches to form a carefully designed and versatile surface (Nature 454, 618–621; 2008).

The team formed a hexagonal network of hydrogen-bonded organic molecules with a period of 3.5 nm on a gold surface (left). Made of two-fold (blue) or three-fold (red) symmetric molecules, the network acted as a template for thiol molecules (black), with the self-assembled monolayers only forming in the open cavities.