For more than two centuries, crystallography was based on an immovable dogma: in any crystal, atoms must be arranged in periodic cells that repeat identically in space, like floor tiles. Mathematically, only two-, three-, four-, or six-fold rotational symmetries were feasible; a five- or ten-fold symmetry was considered an absolute geometric impossibility, as it would leave empty gaps.
On April 8, 1982, Israeli physicist Dan Shechtman was examining a rapidly solidified aluminum and manganese alloy under an electron microscope. The diffraction pattern revealed concentric circles formed by exactly ten equidistant bright dots: perfect pentagonal symmetry. Astonished, Shechtman wrote in his laboratory notebook: «10-fold?» surrounded by question marks.
The discovery sparked crushing rejection from the scientific community:
- His laboratory director sarcastically handed him an elementary physics textbook, urging him to study before spreading nonsense, and eventually expelled him from the research group.
- The world's leading chemical authority, two-time Nobel laureate Linus Pauling, mocked him at conferences, stating: «There are no quasicrystals, only quasi-scientists».
Despite the ostracism, Shechtman persisted. His analyses proved that the atoms were ordered aperiodically, replicating the famous Penrose tilings in three dimensions: a regular mathematical pattern governed by the golden ratio that never repeats itself. Decades later, after natural quasicrystals were found in a meteorite from Kamchatka, the International Union of Crystallography had to change the official definition of a crystal, and Dan Shechtman solely received the Nobel Prize in Chemistry in 2011.
Source: The Nobel Prize in Chemistry 2011 - Scientific Background / Nature Materials
