ABSTRACT
The well ordered world of solid materials was forced to reassess its rules of order by the spectacular results of D. Shechtman, I. Blech, D. Gratias, and J. W. Cahn. By the year 1801, the fundamental laws of crystal morphology had been well established, and in the last two decades of that century, theories of the internal symmetries of crystals were being discussed. In general, crystals are classified according to their allowed translational and rotational symmetry operations. The physical realization of quasicrystals and the intellectual understanding of their formation thus has been achieved. At the foundation of this discovery is the work of Shechtman, Blech, Gratias, and Cahn, which has spawned an entirely new branch of materials science. While quasicrystals remain a major focus of his work, he is also pursuing research on chemical vapor deposited (CVD) diamond wafers, metallic multilayers, and rapidly solidified metallic alloys.
