Walter Kohn was an Austrian-American theoretical physicist and theoretical chemist. He was awarded, with John Pople, the Nobel Prize in Chemistry in 1998. The award recognized their contributions to understanding the electronic properties of materials. In particular, Kohn played the leading role in the development of density functional theory, which made it possible to calculate quantum mechanical electronic structure by equations involving the electronic density. This computational simplification led to more accurate calculations on complex systems as well as many new insights, and it has become an essential tool for materials science, condensed-phase physics, and the chemical physics of atoms and molecules. The Nobel Prize in Chemistry 1998, announced October 13, 1998. Walter Kohn (1/2), “for his development of the density-functional theory”. John Pople (1/2), “for his development of computational methods in quantum chemistry”. Walter Kohn: born 1923, Vienna, Austria. John Pople: born 1925, Burnham-on-Sea, United Kingdom. Wiki link Wiki link Data: the Nobel Foundation (CC0).