Semyonov was born in
Saratov in April 1896, the son of Yelena Dmitrieva and Nikolai Aleksandrovich Semyonov. He graduated from the department of
physics of
Petrograd University (1913–1917), where he was a student of
Abram Fyodorovich Ioffe. After graduating from Saint Petersburg State University, Semyonov worked as an assistant and lecturer in
Tomsk at the
Tomsk University Institute of Technology, where he published his first research paper in 1916. In 1918, he moved to
Samara, where he was enlisted into
Kolchak's
White Army in 1919 during the
Russian Civil War, although he obtained a teaching deferment and managed to avoid service. In December of that same year, he was pressed into the radio service of the Red Army. After his discharge in the winter of 1920, Semyonov obtained work at universities in
Perm and Tomsk. After the war, Semyonov returned to
Petrograd and took charge of the
electron phenomena laboratory of the
Petrograd Physico-Technical Institute, continuing to occasionally travel back to Tomsk as well as at times meeting with officials from
Moscow. He also became the vice-director of the institute. In 1921, he
married philologist Maria Boreishe-Liverovsky (student of
Zhirmunsky). She died two years later. On September 15, 1924, Nikolay married Maria's niece, Natalia Nikolayevna Burtseva. They had two children, son Yuri and 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
adsorption 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. In 1927, Semyonov studied the ionization of gases, the chemistry of the electron. In 1928, he created the theory of the broken discharge of dielectrics with
Vladimir Fock. He lectured at the
Petrograd Polytechnical Institute and was appointed Professor in 1928. In 1931, he organized the Institute of Physical Chemistry of the
USSR Academy of Sciences (which moved to
Chernogolovka in 1943) and became its first director. In 1932, he became a full member of the Soviet Academy of Sciences. The ideas of Semyonov have been applied in the science of reaction and production of polymerization reactions. His ideas are also applied in catalysis studies in biological systems. Semyonov married Natalya Nikolayevna Semyonov and together they both have a son and a daughter. Semyonov died on September 25, 1986, in Moscow, and was buried at the
Novodevichy Cemetery. ==Significant works==