ABSTRACT
Until the 1930s, the leit-motiv of everything dealing with the field opened by Becquerel in 1896 was "radioactivity". Scientists working with radionuclides did not necessarily consider themselves to be physicists or chemists. However, investigation of the physical and chemical properties of matter that emit ionizing radiations either spontaneously or after artificial transformation progressively led to the opening of new fundamental domains. Several frontiers began to emerge, for example, between the chemistry of the newly discovered elements and radionuclides and the physics of the nucleus and its radiations.
