Forty years of quasicrystals: a bumpy road to triumph

Abstract

On April 8, 1982, Dan Shechtman conducted an electron diffraction experiment on an aluminum/manganese alloy. The diffraction pattern showed tenfold symmetry although the rules of crystallography excluded such symmetry in extended structures. Alan L. Mackay had anticipated such structures, which fit his view of generalized crystallography. Shechtman persisted in claiming to have observed quasiperiodic structures despite denial of such structures even by Linus Pauling, the greatest authority in chemistry. When Shechtman’s claim was finally accepted, he was amply awarded for his contribution, including his Nobel Prize in 2011. The theoretical physicists Paul J. Steinhardt and Dove Levine coined the name quasicrystals, and advanced the field greatly by their models, but appeared to downplay somewhat the significance of prior predictions and of the experimental discovery.