Alfred Werner Coordination Chemist

However, in 1890 a young Swiss chemist named Alfred Werner, who had just obtained a Ph.D. in the field of organic chemistry, became so interested in these compounds that he apparently even dreamed about them. In the middle of one night Werner awoke realizing that he had discovered the correct explanation for the constitution of these compounds. Writing furiously the rest of that night and into the late afternoon of the following 

For his work on coordination chemistry and stereochemistry, Werner became the fourteenth Nobel Prize winner in chemistry and the first Swiss chemist to be so honored. Werner s work is even more remarkable when one realizes that his ideas preceded any real understanding of the nature of covalent bonds by many years.  

We now realize that optical activity is exhibited by molecules that have nonsuperimposable mirror images. Your hands are nonsuperimposable mirror images (Fig. 20.15 on page 952). That is, human hands are related like an object and its mirror image and one hand cannot be turned to make it identical to the other. Many molecules show this same feature—for example, 

Unpolarized light consists of waves vibrating in many different planes (indicated by the arrows). The polarizing filter blocks all waves except those vibrating in a given plane. 

The rotation of the plane of polarized light by an optically active substance. The angle of rotation is called theta (6). 

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Metal complexes have characteristic shapes, depending on the metal ion s coordination number. Two-coordinate complexes, such as [Ag(NH3)2]+, are linear. Four-coordinate complexes are either tetrahedral or square planar for example, [Zn(NH3)4]2+ is tetrahedral, and [Ni(CN)4]2 is square planar. Nearly all six-coordinate complexes are octahedral. The more common coordination geometries are illustrated in Figure 20.12. Coordination geometries were first deduced by the Swiss chemist Alfred Werner, who was awarded the 1913 Nobel Prize in chemistry for his pioneering studies. 

Alfred Werner was born in 1866 and died from arteriosclerosis in 1919, He started as an organic chemist and finished his chemical career in 1915 as one of the foremost inorganic chemists,. He won the Nobel Prize in 1913, During a period of two and a half decades he published 174 papers and supervised the work covered by 200 doctoral dissertations, Werner was the founder of coordination chemistry. He rejected the then prevailing concept formulated by Kekule) that the valence of an element is invariable and introduced instead the notion of principal and auxiliary valence. He also formulated the concept of coordination number, Werner used both the inductive and the deductive methods of reasoning. Most of his predictions on geometrical and optical isomerism were verified by experiment. 

The coordination theory was promoted by the Swiss chemist Alfred Werner (1866-1919) in 1891. He became a professor in Zurich in 1893, and in 1913, he received the Nobel Prize in Chemistry for his investigations of complex compounds. Werner found many non-organic compounds with asymmetrical molecules that were also optically active in solutions. Such complex compounds include Co, Cr, and Fe. 

The Alsatian-Swiss chemist Alfred Werner pioneered the field of coordination chemistry in the late nineteenth century. At that time, a number of compounds of cobalt(III) chloride with ammonia were known. They had the following chemical... 

Bonding in transition metal complexes was not understood until the pioneering research of Alfred Werner (1866-1919), a Swiss chemist who received the Nobel Prize in chemistry in 1913. Great advances have been made since in the field of coordination chemistry, but Werner s work remains the most important contribution by a single researcher. 

The stereochemistry of coordination compounds is as old as coordination chemistry itself. The Swiss chemist Alfred Werner (1866-1919) derived the theory of coordination, published in 1893, to a large extent from stereochemical arguments. 

In 1893 the Swiss chemist Alfred Werner (1866—1919) proposed a theory that successfully explained the observations in Table 23.3. In a theory that became the basis for understanding coordination chemistry, Werner proposed that any metal ion exhibits both a primary valence and a secondary valence. The pritnaij valence is the oxidation state of the metal, which is +3 for the complexes in Table 23.3. — (Section 4.4) The secondary valence is the number of atoms bonded to the metal ion, which is also called the coordination number. For these cobalt complexes, Werner deduced a coordination number of 6 with the ligands in an octahedral arrangement around the Co ion. 

The nature and properties of metal complexes have been the subject of important research for many years and continue to intrigue some of the world s best chemists. One of the early Nobel prizes was awarded to Alfred Werner in 1913 for developing the basic concepts of coordination chemistry. The 1983 Nobel prize in chemistry was awarded to Henry Taube of Stanford University for his pioneering research on the mechanisms of inorganic oxidation-reduction reactions. He related rates of both substitution and redox reactions of metal complexes to the electronic structures of the metals, and made extensive experimental studies to test and support these relationships. His contributions are the basis for several sections in Chapter 6 and his concept of inner- and outer-sphere electron transfer is used by scientists worldwide. 

Alfred Werner (1866-1919). Swiss chemist. Werner started as an organic chemist but became interested in coordination chemistry. For his theory of coordination compounds, Werner was awarded the Nobel Prize in Chemistry in 1913. 

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