Complex sentence: At the end of World War II in 1945 Hahn was suspected of working on the German nuclear energy project to develop an atomic reactor or an atomic bomb, but his only connection was the discovery of fission; he did not work on the program.
Split into simpler sentences: At the end of World War II in 1945 Hahn was suspected of working on the German nuclear energy project to develop an atomic reactor or an atomic bomb. But his only connection was the discovery of fission; he did not work on the program.