Barium in irradiated uranium
At the Kaiser Wilhelm Institute for Chemistry in Berlin, Strassmann worked with Hahn. In late 1938 they identified barium among the products of neutron irradiation of uranium. Its much lower mass made the result difficult to reconcile with the expected heavy-element transformations and supplied crucial evidence of nuclear splitting.
From products to fission
Meitner had already fled Nazi Germany. On receiving the experimental findings, she and Otto Frisch provided the physical explanation of nuclear splitting and its energy release. Strassmann’s chemical identification formed the experimental part of this collaborative sequence.
Postwar work in Mainz
From 1946 Strassmann helped rebuild chemical research in Mainz and organise the institute’s move from Tailfingen, completed in 1949. He also developed teaching and research at Mainz University and promoted the TRIGA Mainz reactor. The university programme and the Max Planck institute were connected but distinct institutions.