Shechtman first created quasicrystals by rapidly cooling molten metals, such as aluminium and manganese, by squirting the mixture onto a cool surface. Then, he observed that the new crystal was made up of perfectly ordered, non-repeating units – a structure that is at odds compared with other crystals, which are regular and precisely repeating.
His discovery in 1982 led to controversy that he was asked to leave the research group. However, his battle eventually forced scientists to reconsider their conception of the very nature of matter.
Aperiodic mosaics, such as those found in the medieval Islamic mosaics of the Alhambra Palace in Spain and the Darb-i Imam Shrine in Iran, have helped scientists understand what quasicrystals look like at the atomic level. In those mosaics, as in quasicrystals, the patterns are regular – they follow mathematical rules – but they never repeat themselves.
When scientists describe Shechtman’s quasicrystals, they use a concept that comes from mathematics and art: the golden ratio. This number had already caught the interest of mathematicians in Ancient Greece, as it often appeared in geometry. In quasicrystals, for instance, the ratio of various distances between atoms is related to the golden mean.
Following Shechtman’s discovery, scientists have produced other kinds of quasicrystals in the lab and discovered naturally occurring quasicrystals in mineral samples from a Russian river. A Swedish company has also found quasicrystals in a certain form of steel, where the crystals reinforce the material like armor. Scientists are currently experimenting with using quasicrystals in different products such as frying pans and diesel engines.
Commenting on the discovery, Professor David Phillips, president of the Royal Society of Chemistry, said: “Quasicrystals are a fascinating aspect of chemical and material science – crystals that break all the rules of being a crystal at all.”
So far, 102 Nobel Prizes in Chemistry have been awarded since 1901. It was not awarded on eight occasions: in 1916, 1917, 1919, 924, 1933, 1940, 1941 and 1942. During World War Two, two German Nobel Laureates in Chemistry have been forced by authorities to decline the Nobel Prize.
The Nobel Prize in Chemistry has been awarded to 160 Laureates but as Frederick Sanger has been awarded twice, there are 159 individuals who have received the Nobel Prize in Chemistry since 1901.
The Nobel Foundation’s rulebook says: “A prize amount may be equally divided between two works, each of which is considered to merit a prize. If a work that is being rewarded has been produced by two or three persons, the prize shall be awarded to them jointly. In no case may a prize amount be divided between more than three persons.”
Germany forbade three German Nobel Laureates from receiving the Nobel Prize – two of whom were awarded the Nobel Prize in Chemistry, Richard Kuhn in 1938 and Adolf Butenandt in 1939. The third person, Gerhard Domagk was awarded the Nobel Prize in Physiology or Medicine in 1939. All of them received the Nobel Prize Diploma and Medal later, but not the prize amount.