Lennard Jones, John Edward

John Edward Jones was born in the town of Lee (County Lancashire ), studied at a local grammar school. In 1912, he entered the University of Manchester , where he studied mathematics , studied the problems of sound theory and received a master's degree in science. In 1915 , during the First World War , he joined the Royal Air Force and served in France. He also participated in aerodynamic calculations at the National Physical Laboratory.

In 1919 , after returning from the army, Jones taught mathematics at the University of Manchester, received a doctorate. At this time, his interest in the kinetic theory of gases was born. In 1922, Jones received a scholarship in honor of the World Exhibition of 1851 (see 1851 Research Fellowship ) and got the opportunity to go to Cambridge University , where in 1924 he defended his thesis for a doctorate. The following year, he married Kathleen Lennard and changed his surname to a double - Lennard-Jones. In Cambridge, under the influence of Ralph Fowler, he became interested in the problem of interatomic and intermolecular forces .

In 1925, Lennard-Jones was elected lecturer in mathematical physics at the University of Bristol , and a year and a half later he headed the Department of Theoretical Physics ( Melville Wills Chair of Theoretical Physics ). During 1929, he studied quantum mechanics in Göttingen , after which he began to actively apply this new science to the problem of the structure of molecules and solids . In 1930 - 1932 , Lennard-Jones was the dean of the faculty of sciences of the University of Bristol - this was his first purely administrative position.

In 1932, Lennard-Jones became a professor of theoretical chemistry ( Plummer Chair of Theoretical Chemistry ) in Cambridge, a position specially introduced for him. Here he founded the famous school of theoretical chemistry, many of his students became successful scientists. In 1937, Lennard-Jones was one of the founders of the Cambridge University Mathematics Laboratory (see University of Cambridge Computer Laboratory ), which he headed in the early years of its existence. In 1939, he was one of the initiators of the automation of quantum mechanical calculations, for which a small differential analyzer was created.

After the outbreak of World War II, Lennard-Jones led a group of mathematicians involved in military calculations (ballistic computing), and held various consultative positions in the Ministry of Supply (see Ministry of Supply ). After the war ended, in August 1945, he headed the scientific studies of the Ministry of Supply, was engaged in their transfer to peaceful rails, but a year later decided to return to Cambridge University. Here he came up with a number of initiatives to improve the scientific and educational process. In 1948 - 1950 , he was president of the Faraday Society . In 1947-1954, he was a member of the research department of the London National Gallery .

In 1953, he was invited to take the post of director of North Staffordshire University College, in which an experiment was conducted to reorganize the educational process and administration. The name Lennard-Jones is one of the laboratories of Keele University (former North Staffordshire University College, see Keele University ). The Royal Chemical Society presents the Lennard-Jones Medal.

Lennard-Jones scientific papers are devoted to quantum chemistry , statistical mechanics , and atomic physics . In 1924, he proposed a semi-empirical potential for describing interatomic forces ( Lennard-Jones potential ), which he used to calculate the energy parameters of the crystal lattices of a number of substances. He also interpreted the parameters of the van der Waals equation in terms of intermolecular forces .

Lennard-Jones investigated critical phenomena , developed methods for describing liquids and dense gases. Since 1932, he was engaged in the theory of adsorption , showed the possibility of the formation of covalent bonds between a molecule and an absorbent surface . On this basis, a classification of adsorption species was built.

Lennard-Jones is rightfully considered one of the founders of quantum chemistry . In 1928 - 1932 , along with Friedrich Hund and Robert Mulliken, he laid the foundations of one of the main quantum chemical approaches - the molecular orbitals method . In 1929, he used this approach to diatomic molecules and gave the first justification for the paramagnetism of an oxygen molecule. Later, he developed applications of this method to the study of the structure of various molecules: in 1937 he considered polyenes and aromatic molecules , in a number of articles from 1949 he substantiated the theory of chemical valency . In 1951, he carried out the first calculations of the ionization potentials of organic molecules using the equivalent orbit method .

• Knight Commander of the Order of the British Empire (1946)
• Honorary Doctor of Science, University of Cambridge (1946)
• Davy Medal of the Royal Society of London (1953)
• Hopkins Prize of the Cambridge Philosophical Society (1953)
• Honorary Doctor of the University of Oxford (1954)
• Longstaff Medal of the Chemical Society (1954)

• JE Jones. On the Determination of Molecular Fields. I. From the Variation of the Viscosity of a Gas with Temperature // Proc. R. Soc. Lond. A. - 1924. - T. 106 . - S. 441-462 .
• JE Jones, AE Ingham . On the Calculation of Certain Crystal Potential Constants, and on the Cubic Crystal of Least Potential Energy // Proc. R. Soc. Lond. A. - 1925. - T. 107 . - S. 636-653 .
• WE Garner, JE Lennard-Jones. Molecular Spectra and Molecular Structure. A general discussion // Transactions of the Faraday Society. - 1929. - T. 25 . - S. 611-627 .
• WE Garner, JE Lennard-Jones. Molecular Spectra and Molecular Structure // Nature . - 1929 .-- T. 124 . - S. 584-588 .
• JE Lennard-Jones. The electronic structure of some diatomic molecules // Transactions of the Faraday Society. - 1929. - T. 25 . - S. 668-686 .
• JE Lennard-Jones, AF Devonshire. Diffraction and Selective Adsorption of Atoms at Crystal Surfaces // Nature . - 1936 .-- T. 137 . - S. 1969-1070 .
• JE Lennard-Jones, AF Devonshire. Critical and Co-Operative Phenomena. III. A Theory of Melting and the Structure of Liquids // Proc. R. Soc. Lond. A. - 1939 .-- T. 169 . - S. 317-338 .
• J. Lennard-Jones. The Molecular Orbital Theory of Chemical Valency. I. The Determination of Molecular Orbitals // Proc. R. Soc. Lond. A. - 1949. - T. 198 , No. 1052 . - S. 1-13 .
• GG Hall, J. Lennard-Jones. The Molecular Orbital Theory of Chemical Valency. VII. Molecular Structure in Terms of Equivalent Orbitals // Proc. R. Soc. Lond. A. - 1951. - T. 205 , No. 1082 . - S. 357-374 .

• NF Mott . John Edward Lennard-Jones (1894-1954) // Biographical Memoirs of Fellows of the Royal Society. - 1955. - T. 1 . - S. 174-184 .
• Temples Yu.A. Lennard-Jones, John Edward (Lennard-Jones, Sir John Edward) // Physicists: Biographical Reference / Ed. A.I. Akhiezer . - Ed. 2nd, rev. and add. - M .: Nauka , 1983 .-- S. 160-161. - 400 p. - 200,000 copies. (in per.)
• Lennard-Jones, John Edward // V.A. Volkov, E.A. Vonsky, G.I. Kuznetsova. Outstanding Chemists of the World: A Biographical Directory. - M .: High School, 1991 .-- S. 261 .
• GG Hall. The Lennard-Jones paper of 1929 and the foundations of Molecular Orbital Theory // Adv. Quant. Chem. - 1991 .-- T. 22 . - S. 1 .