Scientists have created the smallest and tightest knot ever, breaking a Guinness World Record. According to New Scientist, the knot is made from gold and crosses itself three times, forming a structure known as trefoil knot. It contains just 54 atoms, including six gold atoms that form its backbone, and could help us understand how knots form in biological systems. Before this, the smallest molecular knot known was reported in 2020 and was made with a chain of 69 atoms, crossing over itself three times.
A study about the discovery has been published in the journal Nature.
The gold knot is the tightest because tightness is measured by dividing the number of atoms in the knot by the number of crossings. Hence, the smaller the ratio is, the tighter the knot. The 69-atom chain had a crossing ratio of 23, but the one discovered by scientists at University of Western Ontario in Canada produced a ratio of 18.
The researchers achieved the record by mixing molecules of two gold atoms linked by carbon rings with another liquid consisting of pairs of phosphorus atoms linked by different proportions of carbon rings.
"We've made many combinations of gold acetylides and phosphine ligands and they've never before given a trefoil knot. We hadn't predicted that this would happen in this case, so it was serendipity," research team head Richard Puddephatt was quoted as saying by the outlet.
The shape of the knot, which looks like a three-leaf clover, is fundamental to mathematical knot theory, as per Science Alert.
The outlet further said that the team created the knot accidentally. Mr Puddephatt and his team were working on creating metal acetylides, but while combining different structures, they unexpectedly created a trefoil knot instead of a gold chain.
