Archibald Scott Couper
Archibald Scott Couper ( born March 31, 1831 in Kirkintilloch, Scotland, † March 11, 1892 ) was a Scottish chemist, who set an early theory of chemical structure and bonding. He developed the idea of tetravalent carbon atoms join together to form large molecules. He was convinced that the bond order of the atoms in a molecule can be determined from its chemical properties.
Life and work
Couper was the only surviving son of a wealthy textile mill owner in Glasgow. He studied at the Universities of Edinburgh and Glasgow and intermittently during the years 1851-54 in Germany. Formally, he began to study chemistry in the fall of 1854 at the University of Berlin. In 1856 he went to the private laboratory of Charles Adolphe Wurtz at the medical faculty in Paris (now the University of Paris V).
Couper published his " New chemical theory " on June 14, 1858 in compressed form in French, then in August 1858 in -depth work in French and English. Couper developed the idea that carbon atoms may combine with each other to follow the rules of valence. He did this independently of a work, in August Kekulé described the same concept. The thesis that the carbon is tetravalent, Kekulé had in 1857 put forward. As a result of a misunderstanding with Wurtz appeared Kekulé work in May 1858 in the first printing, so that the priority as the discoverer of the self-join of the carbon to Kekulé went. As Couper angrily confronted her Wurtz, Wurtz referred him from the laboratory.
In December 1858 Couper was offered an assistant position at the University of Edinburgh. After his disappointment, however, it started to go downhill with Couper health. In May 1859, he suffered a nervous breakdown and went as a private patient in a mental hospital. When he was released in July 1859, it came almost immediately to a relapse, which was declared as a result of a sunstroke. Treatment was continued until November 1862. But Couper health was now so groggy that he was more able to any serious work. The last 30 years of his life were spent in the care of his mother.
Couper research differed in several ways from the Kekulé. Unlike Kekulé he was open to the idea of a divalent carbon. In his essay he was more enlightened than Kekulé formulas show. In two cases, he even suggested heterocyclic formulas, Kekulé who may be affected during the subsequent elucidation of the structure of the benzene ring. Couper adopted as atomic weight of oxygen 8 instead of 16, so that in Couper formulas twice as many oxygen atoms as in those of Kekulé. Couper drew dotted and dashed lines between atoms in its formula, which gives the appearance of subsequent formulas drawings already comes close. In this respect, had his work is likely to impact on the early structure theorist Alexander Mikhailovich Butlerov and Alexander Crum Brown.