Claus, Carl Ernst

He name is frequently written Carl Ernst Claus It is a German name, not a Russian one. 

The next major theory of metal ammines was proposed by Carl Ernst Claus (1796—1864). In 1854, Claus rejected the ammonium theory and suggested a return to Berzelius view of complexes as conjugated compounds. He compared the platinum ammines not with ammonium salts nor with ammonium hydroxide but with metal oxides. He designated the coordinated ammonia molecule as passive, in contrast to the active, alkaline state in the ammonium salts, where it can easily be detected and replaced by other bases . 

Finally, in 1844, Russian chemist Carl Ernst Claus (also known as Karl Karlovich Klaus 1796—1864) gave positive proof of a new element in platinum ores. Many authorities now call Claus the discoverer of the element. Claus suggested calling the element ruthenium, after the ancient name of Russia, Ruthenia. Osann had suggested that name as well. 

Russian chemist Carl Ernst Claus discovers ruthenium. 

Carl Ernst Claus (Dorpat (Tartu) ii January 1796 (O.S.)-24 March 1864) qualified as a pharmacist in St. Petersburg (Leningrad) and Dorpat, and practised in Kazan (1826). In 1831 he became assistant in chemistry in Dorpat but returned to Kazan in 1837 as associate professor of chemistry, professor in 1843. In 1852 he returned to Dorpat as professor of pharmacy, where he continued work on platinum metals. In 1834 he explored with Goebel the steppes between the Urals and the Volga, receiving the Demidov prize, and he also worked on botany. Schofield, Pharm.y.y 1946, clvii, 135 Poggendorff, (i), i, 425 iii, 278 Weeks, (i), 440. 

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