Nikolay Semyonov
Nikolay Nikolayevich Semyonov () (
April 15 (
April 3,
Old Style),
1896 â€"
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.
Semyonov's outstanding work on the mechanism of chemical transformation includes an exhaustive analysis of the application of the
chain theory to varied reactions (
1934–
1954) and, more significantly, to
combustion processes. He proposed a theory of degenerate branching, which led to a better understanding of the phenomena associated with the induction periods of oxidation processes.
Semyonov wrote two important books outlining his work.
Chemical Kinetics and Chain Reactions was published in 1934 with an English edition in
1935. It was the first book in the U.S.S.R. to develop a detailed theory of unbranched and branched chain reactions in chemistry.
Some Problems of Chemical Kinetics and Reactivity, first published in 1954, was revised in
1958; there are also English, American, German, and Chinese editions.
In
1956, he was awarded the
Nobel Prize in Chemistry (together with Sir
Cyril Norman Hinshelwood) for this work. Semyonov also became a
Hero of Socialist Labor twice, received two
Stalin Prizes, five
Orders of Lenin, and many other awards.
*
Biography of Nikolay Semyonov at NobelPrize.org.
*
Semyonov's Nobel Lecture.
*
Semyonov's Biography.
*
Another Semyonov's Biography.
*
Biography - nobelprize.org
*
N.N. Semenov Institute of Chemical Physics
