Nobel Prize in Chemistry · 1998
Walter Kohn
Refugee from Nazi Vienna whose density-functional theory lets computers predict how molecules and materials behave.
The Nobel citation: “for his development of the density-functional theory”
- Born
- March 9, 1923, Vienna, Austria
- Died
- April 19, 2016, Santa Barbara, CA, USA
- Shared with
- John Pople
- Affiliation at the time
- University of California, USA
Chemistry prize
1998
Shared with 1 other laureate.
Age that year
75years
Born in 1923.
Sources cited
17
Fact-checked September 24, 2026.
- In a Vienna high school he got his only C in mathematics. After the Nazis expelled him, two teachers at a Jewish school turned him toward science.
- Interned as an 'enemy alien' at 17, he earned 20 cents a day as a lumberjack in Canadian camps and saved it to buy textbooks on pure mathematics and chemical physics.
- He won the Nobel Prize in Chemistry, yet his last chemistry class was at 17. In Toronto his German nationality kept him out of the chemistry building.
- By 2003 his 1965 paper with Lu Jeu Sham was the most-cited article in more than a century of Physical Review journals. His 1964 paper with Pierre Hohenberg was second.
- His parents, Salomon and Gittel, were killed at Auschwitz. He reached England in 1939 on one of the last Kindertransport children's trains.
The breakthrough
Density-functional theory: calculating matter from its electron density
Everything around us, from medicines to metals, behaves the way it does because of its electrons. Quantum mechanics has described electrons since the 1920s, but its equations track how every electron pushes on every other one. The work grows so fast with each added atom that the most accurate traditional calculations stall at around ten atoms. Kohn called this an 'exponential wall'.
In 1963 and 1964, working in Paris with Pierre Hohenberg, Kohn proved something surprising. You do not need to follow each electron. The electron density, meaning how many electrons are found on average at each point in space, is enough in principle to determine the system's energy and all its other properties. In 1965, with Lu Jeu Sham in San Diego, he turned this into practical equations, now called the Kohn-Sham equations. They swap the tangle of interacting electrons for simpler, independent ones moving in a shared field.
Think of forecasting a city's traffic. You could try to predict every driver's choices, which is hopeless, or you could work from a map of how crowded each street is. DFT works from the crowd map.
One piece, a term for how electrons avoid one another, has to be approximated, and improving it took decades of work by many others. But the payoff is large. DFT's computing time grows only about as the square or cube of the number of atoms, so by 1999 it could handle systems of hundreds to a thousand atoms.[2],[3],[4],[8],[17]
“I cannot imagine how I might have become a scientist without their help.”
What it meant for humanity
DFT turned the quantum theory of electrons into an everyday tool. Before it, highly accurate quantum calculations were practical only for molecules of about ten atoms. With it, researchers can compute the shapes, energies and reactions of molecules and solids with hundreds of atoms. In 1998 the Royal Swedish Academy of Sciences called it one of the most widely used methods in quantum chemistry, able to help explain how enzyme reactions happen. After John Pople, Kohn's co-laureate, added it to his popular Gaussian program in 1992, its use among chemists spread quickly.
The citation record shows how central it became. By 2003 Kohn's 1965 paper with Sham was the most-cited article in more than a century of Physical Review journals, and his 1964 paper with Hohenberg was second. In 2014 Nature counted 12 papers about DFT among the 100 most-cited scientific papers of all time. By 2012 close to 10,000 papers a year were being published on DFT, and Crossref now records more than 110,000 citations of the two founding papers.
In practice, DFT lets scientists study and screen materials on a computer before anyone makes them. Kohn's Nobel lecture showed it explaining how methanol reacts inside zeolites, catalysts widely used in the chemical industry, and pointing toward better materials for turning heat into electricity. The Materials Project, backed by the US Department of Energy, uses DFT to pre-compute the properties of materials to speed the search for better batteries, solar materials and catalysts, and such calculations have predicted new catalysts and lithium-battery materials.
Kohn also gave his time to public causes. He opposed nuclear weapons work at the University of California and, in 2005, produced a documentary about solar power.
- As of 2003 the 1965 Kohn-Sham paper was the most-cited article in the history of the Physical Review journals, and the 1964 Hohenberg-Kohn paper was second. Crossref now records about 60,000 and 50,000 citations of them.[9],[11],[12]
- Nature's 2014 list of the 100 most-cited papers ever included 12 on DFT. Kohn's two founding papers ranked 34th and 39th.[8]
- The Department of Energy-backed Materials Project uses DFT to pre-compute the properties of materials, aiming to speed the discovery of better batteries, solar materials and catalysts.[10],[13],[14]
- His Nobel lecture showed DFT explaining how methanol binds and reacts inside zeolites, catalysts widely used in the chemical industry.[4]
- In 1979 he became founding director of UC Santa Barbara's Institute for Theoretical Physics, now the Kavli Institute, which became a model for similar institutes elsewhere.[5],[6]
- He opposed nuclear weapons work at the University of California, served on the board of the Nuclear Age Peace Foundation, and in 2005 produced 'The Power of the Sun', a documentary about solar energy.[2],[6],[7]
Impact in numbers
Kohn's contribution is a method, not a product, so this profile makes no numerical claim. DFT is used across chemistry, physics, materials science and biochemistry, and its founding papers are among the most-cited in all of science. But counting lives saved or dollars earned would mean separating DFT's part in each battery, catalyst, drug or chip from experiments, other computer methods, faster hardware and the decades of approximations built by others, among them Axel Becke, Robert Parr and John Perdew, and by his co-laureate John Pople. No published estimate does that credibly. What can be said is that DFT made it possible to calculate, rather than only measure, the properties of molecules and materials with hundreds of atoms, and that it now helps scientists screen new materials on a computer before anyone makes them in a lab.
Fundamental scienceTechnologyEnergy
No number is given here on purpose. Some contributions cannot be counted honestly, and we would rather describe them than invent a figure.
The double edge
No harms have been documented from density-functional theory, which is a calculation method used in research. Its main weakness is accuracy. Around the time of the prize, common approximations underestimated the energy gaps of solids, missed weak van der Waals forces and handled strongly correlated materials poorly. In his Nobel lecture Kohn himself named van der Waals forces and strongly interacting electron systems among the cases where DFT still worked poorly. Kohn also campaigned against the University of California's management of nuclear weapons laboratories.
- Minor
Known accuracy limits
DFT is exact in principle, but real calculations depend on approximations. Around 1998, common approximations underestimated the energy gaps of solids, missed weak van der Waals forces and treated strongly correlated materials poorly. In his Nobel lecture Kohn named van der Waals forces and systems dominated by strong electron interactions as weak spots. By 2012 there was progress on some of these problems, but not all.[4],[10]
Against the odds
In 1938 about 192,000 Jews lived in Austria, most of them in Vienna. German troops marched in that March with the enthusiastic support of most of the population, and anti-Jewish laws followed quickly. In November most of Vienna's synagogues were destroyed. By December 1939 only 57,000 Jews remained, mostly because so many had emigrated. In October 1941 the Nazis began mass deportations of those left to ghettos in eastern Europe.
Kohn had just turned 15 at the Anschluss. His father's art-postcard firm was confiscated, though his father had to keep running it without pay, and Walter was expelled from his school. He spent a year at the Jewish Chajes Gymnasium, where two teachers sparked his love of physics and mathematics; both later became victims of the Nazis. In August 1939 he reached England on one of the last Kindertransport children's trains. His parents could not get out. They were killed at Auschwitz.
In 1940 Britain interned him as an 'enemy alien' at 17 and shipped him to camps in Canada, where he studied with fellow internees and passed university entrance exams. Released in 1942, he was barred from the University of Toronto's chemistry building because of his German nationality. Foster families in England and Canada took him in and backed his studies. He served in the Canadian Army and went on to a doctorate at Harvard.
1938
Persecution
After the Anschluss of March 1938 he was expelled from Vienna's Akademisches Gymnasium. The family's art-postcard business was confiscated, but his father was forced to keep managing it without pay.[2]
1939
Exile
In August 1939, three weeks before the Second World War began, he reached England on one of the last Kindertransport trains, which rescued about 10,000 mostly Jewish children. His parents were unable to leave Austria.[2],[5],[6]
—
Family killed
His parents, Salomon and Gittel Kohn, were killed at Auschwitz. Other relatives and several of his teachers were also murdered in the Holocaust.[2],[5]
1940
Imprisonment
In May 1940, at 17, he was interned by Britain as an 'enemy alien', held on the Isle of Man, and shipped in July through U-boat waters to internment camps in Quebec and New Brunswick. He was released only in January 1942.[2]
1942
Discrimination
At the University of Toronto his German nationality barred him from the chemistry building, where war work was under way. Without chemistry courses he could not enroll normally and was admitted as a special student.[2]
Jewish background
Kohn was born into a middle-class Jewish family in Vienna. His father, Salomon, came from Hodonín in Moravia; his mother, Gittel, from Brody in Galicia. Her parents, the Rappaports, were Orthodox Jews, and through them the family kept in touch with traditional Judaism while also taking part in Vienna's secular cultural life. In his Nobel autobiography he wrote that he had a strong Jewish identity and had worked on several Jewish projects, including a Judaic Studies program at UC San Diego. When he died, UC Santa Barbara announced a public funeral service at Congregation B'nai B'rith, a Santa Barbara synagogue.[2],[5],[6],[16]
Key dates
March 9, 1923
March 1938
Nazi Germany annexes Austria. Kohn is expelled from his school and his family's business is confiscated.[2],[15]
August 1939
Reaches England on one of the last Kindertransport children's trains, leaving his parents behind in Vienna.[2],[5],[6]
May 1940
Interned by Britain as an 'enemy alien' and, in July, shipped to internment camps in Canada.[2]
January 1942
Released from internment and taken in by a Toronto family; he then enters the University of Toronto's mathematics and physics program as a special student.[2]
1948
Earns his PhD at Harvard University under Julian Schwinger.[2]
1950
Joins the Carnegie Institute of Technology in Pittsburgh, his base for the next decade.[2],[3]
1957
Becomes a US citizen.[2]
1960
Moves to the University of California, San Diego, where he helps build the physics department and a Judaic Studies program.[2],[6]
1964
Publishes the Hohenberg-Kohn theorem with Pierre Hohenberg, the foundation of density-functional theory.[2],[4]
1965
Publishes the Kohn-Sham equations with Lu Jeu Sham, which make DFT practical.[2],[4]
1979
Becomes founding director of the Institute for Theoretical Physics at UC Santa Barbara.[2],[5]
October 13, 1998
Awarded half of the Nobel Prize in Chemistry for developing density-functional theory, shared with John Pople.[1],[3]
April 19, 2016
Sources
- 1.Walter Kohn - Facts · NobelPrize.org (Nobel Prize Outreach), 1998
- 2.Walter Kohn - Biographical · NobelPrize.org (Nobel Foundation), 1998
- 3.The Nobel Prize in Chemistry 1998 - Press release · Royal Swedish Academy of Sciences via NobelPrize.org, 1998
- 4.Electronic Structure of Matter - Wave Functions and Density Functionals (Nobel Lecture) · NobelPrize.org (Nobel Foundation), 1999
- 5.In Memoriam: Walter Kohn · The UCSB Current, University of California, Santa Barbara, 2016
- 6.Nobelist Walter Kohn: Nice Guy Who Finished First · The UCSB Current, University of California, Santa Barbara, 1998
- 7.Public Invited to Free Screening of New Documentary on Solar Power Produced by Nobel Laureate Walter Kohn · The UCSB Current, University of California, Santa Barbara, 2005
- 8.The top 100 papers (Van Noorden, Maher and Nuzzo) · Nature, 2014
- 9.Citation Statistics From More Than a Century of Physical Review (S. Redner) · arXiv (published in Physics Today, 2005), 2004
- 10.Perspective on density functional theory (K. Burke), J. Chem. Phys. 136, 150901 · arXiv / Journal of Chemical Physics, 2012
- 11.Crossref metadata record and citation count for Kohn and Sham (1965), Phys. Rev. 140, A1133 · Crossref, 1965
- 12.Crossref metadata record and citation count for Hohenberg and Kohn (1964), Phys. Rev. 136, B864 · Crossref, 1964
- 13.Materials Project documentation (home) · The Materials Project
- 14.Materials Project: Calculation Details · The Materials Project
- 15.Austria (Holocaust Encyclopedia) · United States Holocaust Memorial Museum
- 16.Sad News - Professor Walter Kohn (memo from Chancellor Henry T. Yang) · Office of the Chancellor, University of California, Santa Barbara, 2016
- 17.The Nobel Prize in Chemistry 1998 - Advanced information · Royal Swedish Academy of Sciences via NobelPrize.org, 1998
Fact-checked on September 24, 2026 by a separate AI fact-checking pass that re-opened the sources, with 2 corrections made. How we check
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