What is bohr-sommerfeld model of an atom?

Answer 1

With A. Sommerfeld's extension of the Bohr theory in 1915-1916, it was turned into a powerful tool of atomic research and adopted and further developed by German physicists in particular. The new and more general Bohr-Sommerfeld theory described the atom in terms of two quantum numbers, while Bohr had originally used only one quantum number. With this extension the theory provided an explanation of the Stark effect, the ordinary Zeeman effect, and the fine structure of the hydrogen spectrum. Other developments based on X-ray spectroscopy were less successful, as were attempts to understand the structure of the helium atom. Yet, by 1920 nearly all physicists accepted the theory as the only viable framework for atomic and quantum research. But not all agreed: the chapter includes an account of conceptual and other objections against the theory raised by J. Stark in Germany and a few other physicists.

Answer 2

The Bohr-Sommerfeld model of an atom is an extension of Niels Bohr's atomic model. It incorporates the concept of quantized angular momentum by adding elliptical orbits for electrons, rather than the circular orbits in the original Bohr model. It also considers the electron's motion as a wave rather than a particle, resulting in more accurate predictions of atomic spectra.