Hassel (Hassel), Odd( Norwegian chemist, Nobel Prize in Chemistry, 1969)
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Biography Hassel (Hassel), Odd
May 17, 1897, Mr.. - May 5, 1981
Norwegian chemist Odd Hassel was born in Oslo in the family gynecologist Ernst Hassel and Matilda (nцLe Klaveness) Hassel. At the end of the Oslo school, he studied chemistry, mathematics and physics at the University of Oslo, which he graduated in 1920
After a year traveling in France and Italy, is usually practiced at that time among the students, X. continued his studies at Munich University, and then transferred to Berlin University, who was a leading center for research in physics and chemistry. Before X. began their studies here, he had already managed to work in the Institute of Physical Chemistry and Electrochemistry of Kaiser Wilhelm in Berlin.
This institute X. mastered a new method of X-ray analysis. This method was first applied by English physicists U.G. Bragg and U.L. Bragg, allowed the researchers with the impact beam of X-rays on pure crystal of the substance to determine the spatial (three dimensional) structure of molecules. Some portion of X-rays deflected or diffracted, with the participation of electrons of matter, and the results are recorded on photographic film, can be used to determine the atomic structure of matter. The recommendation of the Director of the Berlin Institute of Physical Chemistry and Electrochemistry, Fritz Haber X. received a Rockefeller grant, while still a student at Berlin University.
After receiving in 1924. University of Berlin doctoral X. in 1925. became a teacher of the University of Oslo, and the next year - an assistant professor of physical chemistry and eletrohimii. In 1934, Mr.. H. moved to set up while the Department of Physical Chemistry at the University of Oslo and became its leader.
In 1930. H. began to search for approaches to the determination of the spatial structure of molecules. At that time, the molecules were classified by their composition (the identity of their constituent atoms), or by their configuration (separation of the molecules 'left and right hand', similarly the left and right gloves or shoes). Knowledge of the molecular structure could shed light on the chemical behavior of compounds and the nature of chemical reactions.
X. interested in the molecules of organic compounds, especially the structure of cyclohexane. This compound is a closed chain or ring, consisting of 6 carbon atoms, which are attached 12 atoms of hydrogen. Its cyclic structure is similar to many other important structures of organic molecules, including steroids and most of the carbohydrates. When X-ray diffraction analysis. data confirmed earlier studies showing that the six-membered carbon ring, such as in cyclohexane, may have a structure, usually called configuration 'bath' and 'chair'.
. In 1938, realizing the limited capacity of X-ray analysis, X
. began to apply new techniques such as electron diffraction. He found that, even when cyclohexane is chemically inactive, its molecules move from a state of 'bath' in the 'chair' and back at speeds of up to one million times per second, and the configuration of 'chair', as suggested by H. energetically higher. Determined, as a form of cyclohexane depends on the location of its atoms, he was able to predict the chemical properties of this substance. His work was extremely important, because cyclohexane is a starting material in the synthesis of many organic compounds.
Continuing in the early 40-ies his studies with cyclohexane, X. able to compile some of its conclusions. However, with the beginning of the Second World War, he refused to be published in German scientific journals, and his works were largely unknown to chemists in Western Europe and America. During the occupation of Norway, Germany, University of Oslo was closed and X. together with other patriots, was arrested by the Nazis and remained in custody throughout this time.
After the war, X. continued work on the molecular configurations. In the first 50 years he began to study the physical structure of the charge-transfer. These compounds are formed by the interaction of molecules - electron donors, such as esters, with molecules - electron acceptors, such as chlorine and fluorine. He eventually brought the law, explaining the geometry of certain types of compounds with charge transfer. Subsequently, the English chemist Derek Barton, using the results of X. with cyclohexane, summarized these laws, extending them to the structure and behavior of a wide range of organic molecules. Although X. officially resigned from the University of Oslo in 1964, he was still several years actively continued his scientific work.
X. and Burton in 1969. shared the Nobel Prize in chemistry, delivered to them 'for their contribution to the development of conformational analysis and its application in chemistry'. Arne Fredga, member of the Royal Swedish Academy of Sciences, in his speech at the presentation said: 'A clever piece of work. a six-membered rings served as the foundation for a dynamic stereochemistry '.
Quiet, very reserved, X. hardly knew personally most of his colleagues on the scientific work, rarely attended international scientific conferences. He was not married. H. died on May 15 1981. in Oslo, not having lived only two days before his 84 birthday.
In addition to the Nobel Prize, X. was awarded the prize in memory of the law of mass action Guldberg and Waage, awarded by the Norwegian Chemical Society (1964), and a medal Gunnerusa Norwegian Royal Academy of Sciences (1964). He was an honorary member of the Norwegian Chemical Society and the British Chemical Society and a member of Norway, the Netherlands and the Royal Swedish Academy of Sciences. In 1967. at the request of many prominent scientists from different countries in his honor at the University of Oslo was established by the annual cycle of readings Hasselskih. The Norwegian Government granted him the title of Knight of the Order of St.. Olaf.