Friedrich Hermann Hund (4 February 1896 – 31 March 1997) was a German

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

from

Karlsruhe Karlsruhe ( , , ; South Franconian: ''Kallsruh'') is the third-largest city of the German state (''Land'') of Baden-Württemberg after its capital of Stuttgart and Mannheim, and the 22nd-largest city in the nation, with 308,436 inhabitants. ...

known for his work on atoms and molecules.

Scientific career

Hund worked at the Universities of

Rostock Rostock (), officially the Hanseatic and University City of Rostock (german: link=no, Hanse- und Universitätsstadt Rostock), is the largest city in the German state of Mecklenburg-Vorpommern and lies in the Mecklenburgian part of the state ...

Leipzig Leipzig ( , ; Upper Saxon: ) is the most populous city in the German state of Saxony. Leipzig's population of 605,407 inhabitants (1.1 million in the larger urban zone) as of 2021 places the city as Germany's eighth most populous, as ...

Jena Jena () is a German city and the second largest city in Thuringia. Together with the nearby cities of Erfurt and Weimar, it forms the central metropolitan area of Thuringia with approximately 500,000 inhabitants, while the city itself has a po ...

Frankfurt am Main Frankfurt, officially Frankfurt am Main (; Hessian: , " Frank ford on the Main"), is the most populous city in the German state of Hesse. Its 791,000 inhabitants as of 2022 make it the fifth-most populous city in Germany. Located on it ...

, and

Göttingen Göttingen (, , ; nds, Chöttingen) is a university city in Lower Saxony, central Germany, the capital of the eponymous district. The River Leine runs through it. At the end of 2019, the population was 118,911. General information The ori ...

. Hund worked with such prestigious physicists as Schrödinger, Dirac, Heisenberg,

Max Born Max Born (; 11 December 1882 – 5 January 1970) was a German physicist and mathematician who was instrumental in the development of quantum mechanics. He also made contributions to solid-state physics and optics and supervised the work of a ...

, and Walter Bothe. At that time, he was Born's assistant, working with quantum interpretation of band spectra of

diatomic molecule Diatomic molecules () are molecules composed of only two atoms, of the same or different chemical elements. If a diatomic molecule consists of two atoms of the same element, such as hydrogen () or oxygen (), then it is said to be homonuclear. O ...

After his studies of mathematics, physics, and geography in Marburg and Göttingen, he worked as a private lecturer for theoretical physics in Göttingen (1925), professor in Rostock (1927), Leipzig University (1929), Jena (1946), Frankfurt/Main (1951) and from 1957 again in Göttingen. Additionally, he stayed in Copenhagen (1926) with

Niels Bohr Niels Henrik David Bohr (; 7 October 1885 – 18 November 1962) was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922 ...

and lectured on the atom at

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of highe ...

(1928). He published more than 250 papers and essays in total. Hund made pivotal contributions to quantum theory - especially concerning the structure of the atom and of molecular spectra. In fact, Robert S. Mulliken, who was awarded the 1966 Nobel Prize in chemistry for molecular orbital theory, always proclaimed the great influence Hund's work had on his own and that he would have gladly shared the Nobel prize with Hund. In recognition of the importance of Hund's contributions, MO theory is often referred to as the Hund-Mulliken

MO theory In chemistry, molecular orbital theory (MO theory or MOT) is a method for describing the electronic structure of molecules using quantum mechanics. It was proposed early in the 20th century. In molecular orbital theory, electrons in a molecule ...

Hund's rule of maximum multiplicity Hund's rule of maximum multiplicity is a rule based on observation of atomic spectra, which is used to predict the ground state of an atom or molecule with one or more open electronic shells. The rule states that for a given electron configuratio ...

is another eponym and, in 1926, Hund discovered the so-called tunnel effect or

quantum tunnelling Quantum tunnelling, also known as tunneling ( US) is a quantum mechanical phenomenon whereby a wavefunction can propagate through a potential barrier. The transmission through the barrier can be finite and depends exponentially on the barrie ...

. The Hund's cases, which are particular regimes in diatomic molecular angular momentum coupling, and

Hund's rules In atomic physics, Hund's rules refers to a set of rules that German physicist Friedrich Hund formulated around 1927, which are used to determine the term symbol that corresponds to the ground state of a multi- electron atom. The first rule is ...

, which govern atomic

electron configuration In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals. For example, the electron configuration of the neon ato ...

s, are important in

spectroscopy Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter ...

and

quantum chemistry Quantum chemistry, also called molecular quantum mechanics, is a branch of physical chemistry focused on the application of quantum mechanics to chemical systems, particularly towards the quantum-mechanical calculation of electronic contributions ...

. In chemistry, the first rule,

, is especially important and is often referred to as simply Hund's Rule.

Personal life

Friedrich Hund is buried in

Munich Waldfriedhof The Munich Waldfriedhof is one of 29 cemeteries of Munich in Bavaria, Germany. It is one of the larger and more famous burial sites of the city, known for its park-like design and tombs of notable personalities. The Waldfriedhof is considered th ...

. He was a member of the International Academy of Quantum Molecular Science. His son is chess player and mathematician

Gerhard Hund Gerhard Friedrich Hund (born February 4, 1932 in Leipzig) is a German chess player, mathematician and computer scientist. Biography He is the oldest son of physicist Friedrich Hund (1896–1997). He studied at the Friedrich Schiller Universi ...

Legacy

On the occasion of his 100th birthday, the book: Friedrich Hund: Geschichte der physikalischen Begriffe istory of Physical Concepts(Heidelberg, Berlin, Oxford), Spektrum, Akademie Verlag 1996, was published. A review was also written by

Werner Kutzelnigg Werner Kutzelnigg (September 10, 1933 – November 24, 2019 in Bochum) was a prominent Austrian-born theoretical chemist and professor in the Chemistry Faculty, Ruhr-Universität Bochum, Germany. Kutzelnigg was born in Vienna. His most signific ...

Grabstein Familien Hund & Pfirsch München

In addition to the many honors bestowed upon him, Friedrich Hund became an honorary citizen of Jena/Saale, and a street in Jena was named after him. In June 2004, a part of a new building of the Physics Department in Göttingen was given the address Friedrich-Hund-Platz 1. The same name was chosen for the Institute for Theoretical Physics at the University of Göttingen.

Publications

* ''Versuch einer Deutung der großen Durchlässigkeit einiger Edelgase für sehr langsame Elektronen'', Dissertation, Universität Göttingen 1923 * ''Linienspektren und periodisches System der Elemente'', Habil.Schrift, Universität Göttingen, Springer 1927 * ''Allgemeine Quantenmechanik des Atom- und Molekelbaues'', in Handbuch der Physik, Band 24/1, 2nd edn., pp. 561–694 (1933) * ''Materie als Feld'', Berlin, Springer 1954 * ''Einführung in die Theoretische Physik'', 5 vols. 1944-51, Meyers Kleine Handbücher, Leipzig, Bibliographisches Institut, 1945, 1950/51 (vol. 1: Mechanik, vol. 2: Theorie der Elektrizität und des Magnetismus, vol. 3: Optik, vol. 4: Theorie der Wärme, vol. 5: Atom- und Quantentheorie) * ''Theoretische Physik'', 3 vols., Stuttgart Teubner, zuerst 1956-57, vol. 1: Mechanik, 5th edn. 1962, vol. 2: Theorie der Elektrizität und des Lichts, Relativitätstheorie, 4th edn. 1963, vol. 3: Wärmelehre und Quantentheorie, 3rd edn. 1966 * ''Theorie des Aufbaues der Materie'', Stuttgart, Teubner 1961 * ''Grundbegriffe der Physik'', Mannheim, Bibliographisches Institut 1969, 2nd edn. 1979 * ''Geschichte der Quantentheorie'', 1967, 2nd edn., Mannheim, Bibliographisches Institut 1975, 3rd edn. 1984; Eng. trans. 1974 * ''Quantenmechanik der Atome'', in Handbuch der Physik/Encyclopedia of Physics, Band XXXVI, Berlin, Springer 1956 * ''Die Geschichte der Göttinger Physik'', Vandenhoeck und Ruprecht 1987 (Göttinger Universitätsreden) * ''Geschichte der physikalischen Begriffe'', 1968, 2nd edn. (2 vols.), Mannheim, Bibliographisches Institut 1978 (vol. 1: Die Entstehung des mechanischen Naturbildes, vol. 2: Die Wege zum heutigen Naturbild), Spektrum Verlag 1996 * ''Göttingen, Kopenhagen, Leipzig im Rückblick'', in

Fritz Bopp Friedrich Arnold "Fritz" Bopp (27 December 1909 – 14 November 1987) was a German theoretical physicist who contributed to nuclear physics and quantum field theory. He worked at the '' Kaiser-Wilhelm Institut für Physik'' and with the '' Ura ...

(ed.) ''Werner Heisenberg und die Physik unserer Zeit'', Braunschweig 1961 * See als
''Verzeichnis der Schriften Friedrich Hund (1896-1997)''
with about 300 entries

References

External links

Curriculum vitae, papers, diploma, honours, medals and decorations, photography, films and cassettes of Friedrich Hund
by