Walter Kohn was a pioneering theoretical physicist whose foundational work transformed our understanding of electronic structures in materials. Born in Vienna, Austria on March 9, 1923, he fled Nazi persecution as a teenager and earned his PhD in physics from Harvard University in 1948 under Nobel laureate Julian Schwinger. He established his academic career at Carnegie Mellon University from 1950 to 1960 before becoming one of the founding faculty members of the Department of Physics at the newly established UC San Diego campus in 1960, where he served as department chair from 1961 to 1963. In 1979, he moved to UC Santa Barbara to become the founding director of what is now the Kavli Institute for Theoretical Physics, a position he held until his death on April 19, 2016 in Santa Barbara at the age of 93.
Kohn's most revolutionary contribution was the development of density functional theory, for which he was awarded the 1998 Nobel Prize in Chemistry, making him the first of six Nobel Laureates at UC Santa Barbara. This theoretical framework fundamentally transformed scientists' approach to understanding the electronic structure of atoms, molecules, and solid materials across physics, chemistry, and materials science. He also developed the Kohn-Korringa-Rostoker method for computing electronic band structures in metals and pioneered the theory of Kohn anomalies that revealed how the Fermi surface manifests as singular features in vibrational spectra. With the advent of supercomputers, density functional theory has become an essential computational tool, with approximately half of the world's publications in quantum chemistry referencing his groundbreaking work.
As founding director of the Institute for Theoretical Physics at UC Santa Barbara, Kohn established one of the world's premier research centers that brought together leading scientists to address fundamental problems in theoretical physics. His legacy extends beyond his Nobel-winning work, as he made significant contributions to semiconductor physics, superconductivity, surface physics, and catalysis throughout his career. In his later years, Kohn expanded his research interests to address societal challenges including macular degeneration, global warming, and renewable energy, co-producing a documentary on solar power titled The Power of the Sun in 2005. Today, Kohn Hall at UC Santa Barbara stands as a lasting tribute to his scientific vision, and his density functional theory continues to underpin cutting-edge research in materials design, quantum chemistry, and nanotechnology worldwide.
