Why did Bohr's model work for 1 electron systems?

In summary, the Bohr model of the atom had three main problems: the assumption of fixed orbits for the electron, the violation of the Heisenberg uncertainty principle with the assumption of constant angular momentum, and the limitation to only 1-electron systems. It failed when applied to poly-electron systems due to the more complex charge interactions. The Pauli exclusion principle also plays a role in this failure. Additionally, the model did not account for the de Broglie wavelength, which was not introduced until later. Arnold Sommerfeld attempted to improve the model by generalizing the orbits to elliptical and incorporating special relativistic dynamics, but it still did not work for all 1-electron systems.
  • #1
mahrap
37
0
If I am not mistaken the Bohr model had 3 main problems: the assumption that the electron moves in fixed orbits, the angular momentum assumption's violation of the Heisenberg uncertainty principle, and finally the restriction of the validity of the model for only 1-electron systems ( i.e. hydrogen, He +1, ect ). Why was it that Bohr's model only worked for 1-electron systems and failed when applied to poly-electron systems? Please be as thorough as possible. Thank you for all your help.
 
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  • #2
nothing stops multiple electrons from being in the same quantum state.
 
  • #3
chill_factor said:
nothing stops multiple electrons from being in the same quantum state.

Nothing but Pauli exclusion principle?
 
  • #4
mahrap said:
failed when applied to poly-electron systems?

What happens when you put two negatively charged object close to each other?
 
  • #5
Borek said:
Nothing but Pauli exclusion principle?

that is not part of the Bohr theory =)
 
  • #6
mahrap said:
Why was it that Bohr's model only worked for 1-electron systems and failed when applied to poly-electron systems?

As Borek has already alluded to, the answer is that systems with more than one electron have a much more complicated charge interaction.

As an interesting side note, the context of Bohr's work is misrepresented when it's taught at schools. At the time he published his model (1913) there was no concept of a de Broglie wavelength. The idea of electron orbits as standing waves wasn't introduced until de Broglie published his thesis in 1924.
 
  • #7
It does not even work for all one electron systems e.g. H2+.
 
  • #8
Arnold Sommerfeld cured two shortcomings: the plane motion was generalized to elliptic orbits and moreover in agreement with the specially relativistic dynamics.
 

FAQ: Why did Bohr's model work for 1 electron systems?

1. Why did Bohr's model only work for 1 electron systems?

Bohr's model successfully explained the behavior of 1 electron systems because it was based on the assumption that electrons move around the nucleus in circular orbits at fixed distances. However, this model fails to accurately describe the behavior of atoms with more than one electron, as electrons in these systems do not move in such predictable orbits.

2. What was the significance of Bohr's model in understanding atomic structure?

Bohr's model was significant because it was the first model to successfully explain the stability and spectral lines of atoms. It also introduced the concept of quantized energy levels, which is a fundamental principle in modern atomic theory.

3. How did Bohr's model contribute to the development of quantum mechanics?

Bohr's model served as a starting point for the development of quantum mechanics, specifically the study of the behavior of particles on a microscopic level. The principles of quantized energy levels and the wave-particle duality of electrons proposed in Bohr's model were further developed and refined in quantum mechanics.

4. What were the limitations of Bohr's model?

One of the main limitations of Bohr's model was that it could not accurately predict the behavior of atoms with more than one electron. It also failed to explain the fine structure of spectral lines and the behavior of atoms in highly excited states.

5. How has our understanding of atomic structure evolved since Bohr's model?

Since Bohr's model, our understanding of atomic structure has evolved significantly. We now know that electrons do not move in fixed orbits, but rather exist in a probability cloud around the nucleus. This is described by the quantum mechanical model of the atom, which takes into account the wave-like properties of particles and provides a more accurate description of atomic behavior.

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