Otto Hönigschmid (13 March 1878 in Hořovice – 14 October 1945 in Munich) was a Czech/Austrian chemist. He published the first widely accepted experimental proof of isotopes along with Stefanie Horovitz.

Education

Hönigschmid studied organic chemistry at the Charles University in Prague under the guidance of Guido Goldschmiedt (the discoverer of the structure of papaverine). Additionally, he worked as a student researcher in Paris under Henri Moissan from 1904 to 1906. During this year he learned Richards' Nobel Prize winning methods for precisely determining atomic weights, which earned Hönigschmid credibility in the field.

From 1911-18 where he founded a laboratory specifically for research with atomic weights. He and his colleagues worked up until 1941 to precisely define atomic weights of over 40 elements. Notable contributions redefined values for silver, niobium, tantalum, and phosphorus. Additionally, he served as the chairman of the German Atomic Weight Commission from 1920-1930, and in 1930 became the German representative in the Atomic Weights Committee of the International Union of Chemistry. This work was instrumental in the adoption of precisely defined atomic weights in the international scientific community. and the Liebig Medal in 1940.

Death

Much of Hönigschmid's work, his home, and his laboratory in Munich were destroyed during World War II. Facing difficulties with his health and housing, he committed suicide alongside his wife in 1945.