Comment on "Coordination-Driven Self-Assembly of a Molecular Knot Comprising Sixteen Crossings".

The remarkable metalla-knot obtained by Kim, Jung, Chi and colleagues is an 818 knot, a metalla-knot that comprises eight crossings, not sixteen. It is the first knot to be synthesized having the 818 topology. Like several previous molecular knots, it adopts a conformation that does not correspond to the reduced form of the knot and has additional persistent nugatory crossings.