The Austrian nuclear physicist was one of those men who was said to have been able to build the atomic bomb in Germany during World War II if sufficient funds had been made available. Harteck studied at the University of Vienna, then moved to Berlin University, where he graduated in 1926. He worked at the Kaiser Wilhelm Institute for Physical Chemistry in Berlin-Dahlem under Fritz Haber from 1928.
Between 1934 and 1951 he was a member of the faculty of the University of Hamburg. For a time he worked with Otto Hahn and Werner Heisenberg in the field of atomic disintegration in Berlin at the institute of the then Kaiser Wilhelm Society.
Harteck worked in the fields of vapor pressure measurements, photochemistry, hydrogen, thermodynamics, atomic physics, on high and low temperatures, on gas centrifuges, on physical and chemical problems of the atmosphere, on spectroscopic investigations and radiation research, and on the atmosphere of planets.