Semyonov (right) and Kapitsa, portrait by Boris Kustodiev, 1921.
||April 15 (April 3
||September 25, 1986
||physicist and chemist
||Nobel Prize in chemistry 1956
Nikolay Nikolayevich Semyonov (Russian: Никола́й Никола́евич Семёнов) (April 15 (April 3, Old Style), 1896 – September 25, 1986 ) was a Russian/Soviet physicist and chemist. Semyonov was awarded the 1956 Nobel Prize in chemistry for his work on the mechanism of chemical transformation.
Semyonov was born in Saratov and graduated from the department of physics of Petrograd University (1913–1917), where he was a student of Abram Fyodorovich Ioffe. In 1918, he moved to Samara, where he was enlisted into Kolchak's White Army during Russian Civil War.
In 1920, he returned to Petrograd and took charge of the electron phenomena laboratory of the Petrograd Physico-Technical Institute. He also became he vice-director of the intstitute. In 1921, he married philologist Maria Boreishe-Liverovsky (student of Zhirmunsky). She died two years later. In 1923, Nikolay married Maria's niece Natalia Nikolayevna Burtseva. She brought Nikolay a son (Yuri) and a daughter (Lyudmila).
During that difficult time, Semyonov, together with Pyotr Kapitsa, discovered a way to measure the magnetic field of an atomic nucleus (1922). Later the experimental setup was improved by Otto Stern and Walther Gerlach and became known as Stern-Gerlach experiment.
In 1925, Semyonov, together with Yakov Frenkel, studied kinetics of condensation and adsorbtion of vapors. In 1927, he studied ionisation in gases and published an important book, Chemistry of the Electron. In 1928, he, together with Vladimir Fock, created a theory of thermal disruptive discharge of dielectrics.
He lectured at the Petrograd Polytechnical Institute and was appointed Professor in 1928. In 1931, he organized the Institute of Chemical Physics of the U.S.S.R. Academy of Sciences (which has moved to Chernogolovka in 1943) and became its first director. In 1932, he became a full member of the Soviet Academy of Sciences.