Polanyi , John Charles

Polanyi , John Charles
(1929–) Canadian chemist
John Polanyi was the son of the distinguished physical chemist Michael Polanyi. Born in Berlin, Germany, he was educated at Manchester University and at Princeton, where he obtained his PhD in 1952. He moved soon after to Toronto University, being appointed professor of chemistry in 1962.
Beginning in the 1950s Polanyi has sought to throw light on the nature of chemical reactions. What actually happens, he asked, during the reaction H + Cl2 -> HCl + Cl? The reaction was known to be strongly exothermic; it was not known, however, how this released energy was distributed in the various degrees of freedom of the reaction products. D. Herschbach had begun detailed investigations of reaction mechanics by measuring the velocities and angular distribution of the reaction products using molecular beams. In contrast Polanyi described his own method as one in which “the molecules formed in chemical reaction do the work by signaling to us their state of excitation…through infrared emission.”
Initially Polanyi and his coworkers had to work with a detector “only slightly more sensitive than the palms of our hands…a thermocouple.” They were soon able to replace this with semiconductor infrared detectors. By analyzing the infrared emission, Polanyi was able to measure how much of the reaction energy was stored as molecular vibration and rotation. In this way he was able to show that in the example cited above two distinct states of the molecule HCl were formed: one with high vibrational and rotational excitation, but low translational energy; and the less common state with low vibrational and rotational energy but high translational energy. Polanyi has continued to work in the field of reaction dynamics and has developed many new techniques and derived numerous insights into the subject. For his contributions he shared the 1986 Nobel Prize for chemistry with Herschbach and Y. T. Lee.
Polanyi's work in infrared chemical luminescence led to the development of chemical lasers by G. Pimental and J. Kaspar in 1960.

Scientists. . 2011.

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  • John Charles Polanyi — (* 23. Januar 1929 in Berlin) ist ein in Deutschland geborener kanadischer Chemiker und Physiker ungarischer Abstammung und Sohn des Wissenschaftlers und Philosophen Michael Polanyi. Er erhielt 1986 den Nobelpreis für Chemie. Leben Polanyi… …   Deutsch Wikipedia

  • John Charles Polanyi — Pour les articles homonymes, voir Polanyi. John Charles Polanyi (23 janvier 1929 à Berlin) est un chimiste et physicien canadien. Il obtint le prix Nobel de chimie de 1986 conjointement avec Yuan Tseh Lee et Dudley Robert Herschbach… …   Wikipédia en Français

  • John Charles Polanyi — John Charles Polanyi,, (in Hungarian Polányi János) PC, CC, FRSC, FRS (born January 23, 1929) is a Hungarian Canadian chemist.He was born in Berlin, son of distinguished Hungarian chemist Michael Polanyi and Magda Elizabeth Polanyi, and nephew of …   Wikipedia

  • Polanyi, John C. — ▪ Canadian chemist and educator in full  John Charles Polanyi   born Jan. 23, 1929, Berlin, Ger.       chemist and educator who, with Dudley R. Herschbach (Herschbach, Dudley R.) and Yuan T. Lee (Lee, Yuan T.), received the Nobel Prize for… …   Universalium

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  • Polanyi — Polanyi, John Charles …   Enciclopedia Universal

  • Chemienobelpreis 1986: Dudley Robert Herschbach — Yuan Tseh Lee — John Charles Polanyi —   Die drei amerikanischen Wissenschaftler erhielten den Nobelpreis für ihre Arbeiten zur Dynamik chemischer Elementarprozesse.    Biografien   Dudley Robert Herschbach, * San José (Kalifornien) 18. 6. 1932; 1958 Promotion an der …   Universal-Lexikon

  • John C. Polanyi — John Charles Polanyi Pour les articles homonymes, voir Polanyi. John Charles Polanyi (né le 23 janvier 1929 à Berlin), est un chimiste et physicien canadien. En 1986, il obtint conjointement avec Dudley R. Herschbach et Yuan T. Lee le prix Nobel… …   Wikipédia en Français

  • John Polanyi — John Charles Polanyi Pour les articles homonymes, voir Polanyi. John Charles Polanyi (né le 23 janvier 1929 à Berlin), est un chimiste et physicien canadien. En 1986, il obtint conjointement avec Dudley R. Herschbach et Yuan T. Lee le prix Nobel… …   Wikipédia en Français

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