Bohr's Atomic Model

The model of Niels Bohr (1885–1962) for the atom is since long just the one and only conception for atoms of the vast majority of educated people. The picture of ► electrons revolving round a nucleus on select avenues has become the icon of the atomic age. In stark contrast to this omnipresence, historically, the Bohr atom may be identified as the best available theory for the atom only for a period of roughly ten years between 1914 and 1924. For this reason any consideration of Bohr's atom has to take into account both the historical context of its creation and the long and diverse processes of reception within science, education and public that gave rise to much misinterpretation of Bohr's intentions, his actual work and its physical or realistic interpretation.

For the question of the genesis of the Bohr model one has to go back to the beginning of the twentieth century, when it became widely recognized that both atoms contain electrons and at the same time were almost fully penetrable by electron bombardment. Between 1901 and 1905 various physicists and science popularizers draw the analogy between atoms and planetary systems (e.g. Jean Perrin (1870–1942), Wilhelm Meyer (1853–1910), or Hantaro Nagaoka (1856–1950) ► atomic models) and some of them immediately realized the difference: Since electric forces were both attractive and repulsive it was hard to understand how stable configurations could result at all. As a consequence in the years before world war I concern with detailed atomic models was not widespread. For this reason also the ► Rutherford atom was largely ignored until it could be reinterpreted as a predecessor of the Bohr atom. The favorite heuristic models for the atom in the years around 1910 also for Bohr was Thomson's that came in various imprecise and at times conflicting variations but was nonetheless able to serve in this way the purpose in helping to conceptualize stability, light emission and the existence of a periodic system of elements.