Denis Gratias

Denis Gratias, born on 22 September 1947 in Paris (France) is a French scientist, emeritus research director at the CNRS. His speciality is materials science, in particular crystallography. Since the discovery of quasicrystals by Dan Shechtman in 1982, he has contributed to their description, notably by developing theoretical models. He is a correspondent member at the French Academy of Sciences since 1994. Provided by Wikipedia