Forget diamond, gold and plutonium, because scientists at Oxford University have created a material with a price tag that dwarfs all of the finest substances money can buy. At a recent auction, 200 micrograms of the material fetched £22,000 ($33,000), which works out at around $4.2 billion per ounce.
The material in question consists of molecular units called endohedral fullerenes. These are spheres of carbon atoms, inside which are housed other molecules. Though several variations of endohedral fullerenes have previously been manufactured, the specific types created by the Oxford-based team are thought to be of particular value in the construction of atomic clocks and GPS devices. More specifically, these include N@C60 and N@C70, which consist of a nitrogen atom caged within a carbon sphere made up of 60 and 70 atoms respectively.
Atomic clocks have traditionally been constructed using caesium atoms, which contain 55 electrons arranged in several orbits around the nucleus of the atom. As electrons switch between different orbits, they release radio waves with a very specific and unchangeable frequency. Since this frequency is always exactly the same every time the electrons make this switch, it provides a reliable and constant benchmark for measuring time, and is more accurate than the rotation of the Earth or the swing of a pendulum, both of which can vary slightly.
However, the team behind these endohedral fullerenes believe their material can be used to create an even more reliable atomic clock. At the same time, they claim it can help to develop GPS devices which can track locations to within one millimeter. This could have major implications for the automobile industry, enabling the manufacture of self-driving cars which are capable of monitoring their own movement with great precision.
Speaking to the Telegraph, Dr. Kyriakos Porfyrakis, who founded Oxford University’s company Designer Carbon Materials which created the structures, said they could be used to manufacture a “miniaturized atomic clock that you could carry around in your smartphone.” This would mark a major improvement on current versions of the atomic clock, which is the size of a small room.
However, while endohedral fullerenes may be the most expensive material in existence in today’s market, Forbes has estimated that antimatter – which may one day be used to fuel spaceships – could cost up to $2,800 trillion per ounce.