- David Leigh, Jonathan J. Danon, Anneke Krüger, Jean-François Lemonnier, Alexander J. Stephens, Iñigo J. Vitorica-Yrezabal, Steffen L. Woltering
- 2.5 nanometre(s)
- United Kingdom (Manchester)
The tightest knotted structure is 2.5 nanometres per crossing, achieved by David Leigh, Jonathan J. Danon, Alexander J. Stephens (all UK), Steffen L. Woltering (Germany), Jean-Francois Lemonnier (France), Anneke Krüger (South Africa) and Iñigo J. Vitorica-Yrezabal (Spain), in University of Manchester, Manchester, United Kingdom, on 12 January 2017.
Knotting is a scientific technique that can induce changes in the molecule's properties. Only four prime knot formations have been created out of more than 6 billion: the trefoil, the figure-eight, the pentafoil and now the 819.
Octahedral iron(II) ions control the relative positions of the three strands at each crossing point in a circular triple helicate, while structural constraints on the ligands determine the braiding connections. This approach enables two-step assembly of a molecular 819 knot featuring eight non-alternating crossings in a 192-atom closed loop ~20 nanometers in length. Therefore the knot has 24 atoms (~2.5 nanometers) per crossing.