Templates are widely used to arrange molecular components so they can be covalently linked into complex molecules that are not readily accessible by classical synthetic methods. Nature uses sophisticated templates such as the ribosome, whereas chemists use simple ions or small molecules. But as we tackle the synthesis of larger targets, we require larger templates-which themselves become synthetically challenging. Here we show that Vernier complexes can solve this problem: if the number of binding sites on the template, n(T), is not a multiple of the number of binding sites on the molecular building blocks, n(B), then small templates can direct the assembly of relatively large Vernier complexes where the number of binding sites in the product, n(P), is the lowest common multiple of n(B) and n(T) (refs 8, 9). We illustrate the value of this concept for the covalent synthesis of challenging targets by using a simple six-site template to direct the synthesis of a 12-porphyrin nano-ring with a diameter of 4.7 nm, thus establishing Vernier templating as a powerful new strategy for the synthesis of large monodisperse macromolecules.

The spontaneous ordering of molecules into two-dimensional self-assembled arrays is commonly stabilized by directional intermolecular interactions that may be promoted by the addition of specific chemical side groups to a molecule. In this paper, we show that self-assembly may also be driven by anisotropic interactions that arise from the three-dimensional shape of a complex molecule. We study the molecule mn 12 o 12 (o 2 CCH 3 ) 16 (H 2 o) 4 (mn 12 (acetate) 16 ), which is transferred from solution onto a Au(111) substrate held in ultrahigh vacuum using electrospray deposition (uHV-EsD). The deposited mn 12 (acetate) 16 molecules form filamentary aggregates because of the anisotropic nature of the molecule-molecule and molecule-substrate interactions, as confirmed by molecular dynamics calculations. The fragile mn 12 o 12 core of the mn 12 (acetate) 16 molecule is compatible with the uHV-EsD process, which we demonstrate using near-edge X-ray adsorption fine-structure spectroscopy. uHV-EsD of mn 12 (acetate) 16 onto a surface that has been prepatterned with a hydrogen-bonded supramolecular network provides additional control of lateral organization.

A second generation motorized nanocar was designed, synthesized, and imaged. To verify structural integrity, NMR-based COSY, NOESY, DEPT, HSQC, and HMBC experiments were conducted on the intermediate motor. All signals in (1)H NMR were unambiguously assigned, and the results were consistent with the helical structure of the motor. The nanocar was deposited on a Cu(111) surface, and single intact molecules were imaged by scanning tunneling microscopy (STM) at 5.7 K, thereby paving the way for future single-molecule studies of this motorized nanocar atop planar substrates.

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Controlled self-assembly and chemical tailoring of bimolecular networks on surfaces is demonstrated using structural derivatives of 3,4:9,10-perylenetetracarboxylic diimide (PTCDI) combined with melamine (1,3,5-triazine-2,4,6-triamine). Two functionalised PTCDI derivatives have been synthesised, Br(2)-PTCDI and di(propylthio)-PTCDI, through attachment of chemical side groups to the perylene core. Self-assembled structures formed by these molecules on a Ag-Si(111)sqrt3 x sqrt3R30 degrees surface were studied with a room-temperature scanning tunneling microscope under ultrahigh vacuum conditions. It is shown that the introduction of side groups can have a significant effect upon both the structures formed, notably in the case of di(propylthio)-PTCDI which forms a previously unreported unimolecular hexagonal arrangement, and their entrapment behaviour. These results demonstrate a new route of functionalisation for network pores, opening up the possibility of designing nanostructured surface structures with chemical selectivity and applications in nanostructure templating.