Carbon is known as the hardest element on Earth, and now it seems it could be our squishiest as well.
New research overturns the long-held belief that gels are always made from at least two components, a solvent and a solid, binding the substance together in loose networks.
Dr Patrick Royall at the University of Bristol in the UK and Dr Stephen Williams, of the Research School of Chemistry at the Australian National University, have discovered that C60, the spherical form of carbon, can transform itself into a gel.
C60, which has a crystal lattice of interlocking pentagons and hexagons just like an old-fashioned soccer ball, is commonly referred to as a buckyball.
The paper by Royall and Williams has been accepted for publication in a special edition of the Journal of Physical Chemistry C.
Williams says their finding is based on computer simulations, which show C60 can form into a stable gel if heated rapidly to just over 2000°C and then cooled in less than a billionth of a second to about 27°C.
The computer simulations showed that the C60 gel formed in 10 nanoseconds. The loosely connected solid network that emerged behaved like a wobbly gel. The simulation showed it to be stable at room temperature for at least 100 nanoseconds, which was the longest the simulations ran.
Williams believes the gel could remain stable for even longer at lower temperatures.
"If you drop the temperature a fraction more it should become stable for a lot longer," he says.
He says under low density and high temperatures, C60 "gets to the point where it wants to go from being a gas to a liquid".
During this so-called phase separation, he says, the molecules form a network of clusters that do not fit together, but are bound together by liquid droplets.
The finding means carbon can not only form diamond, graphite, graphene and an infinite number of carbon 'chickenwire' structures such as tubes and footballs, it can also be a jelly.
Entirely theoretical at this stage
Williams says he does not know if it will be possible to prove the simulation experimentally, mainly due to the difficulty of cooling the molecule quickly enough and stopping the process at the correct temperature.
But he says the finding opens the door to asking whether other elements can also make single-component gels.
"If C60 can do it other things should be able to do it as well," says Williams.