abstract-kragh – Niels Bohr Archive

Helge Kragh, University of Aarhus, Denmark
The Many Faces of the Bohr Atom

The atomic model that Bohr proposed in 1913 constituted a break with all earlier models of the atom. Keeping to the theory’s basic postulates, he conceived the model as preliminary and immediately began developing and modifying it. Strictly speaking there was no “Bohr atom” but rather a series of different models sharing some common features. There is a great deal of difference between the 1913 Bohr “pancake model,” the 1922 many-quantum orbital model, and the more symbolic and unvisualizable 1924 model associated with the Bohr – Kramers – Slater theory. I shall pay particular attention to the second of these models which Bohr ambitiously used in describing the electron configurations of all elements in the periodic table. It is still something of a mystery how he arrived at these configurations and how seriously he took the model as a realistic picture of the atom.