How is Bohr's atom model convenient with quantum mechanics?

[Karagoz]

Hi.

From what I read, according to Quantum mechanics "even though it looks like objects are in definite places, when we get down to ridiculously tiny objects (like electrons) they seem to be not he in anyone place. And everything looks like a hazy clouds of probability."

https://www.quora.com/What-is-quantum-physics-in-the-most-layman-terms/answer/Henry-Rasia?srid=33Qhr

And Niels Bohr wasn't against quantum mechanics.

But doesn't it contradict with Bohr's atom model, where in his model electrons move in fixed orbits around the nuclei?

Isn't the "elctron cloud model" more convenient with quantum mechanics?

 

[Drakkith]

But doesn't it contradict with Bohr's atom model, where in his model electrons move in fixed orbits around the nuclei?

Isn't the "elctron cloud model" more convenient with quantum mechanics?

Yes. Bohr's model was made before Quantum Mechanics was fully developed. It is just a stepping stone on the road from classical mechanics to quantum mechanics.

 

[jtbell]

Bohr model: 1913
Schrödinger equation: 1926

 

[vanhees71]

Yes, and Bohr himself, was very happy with modern QT, defending it against serious doubts by great physicists like Einstein and Schrödinger. Bohr knew very well that his model was ad hoc and not a complete theory to begin with. Then it turned out, particularly by tedious work of the Sommerfeld school in Munich, trying to understand the spectra of other atoms than hydrogen using Bohr's original model, that it doesn't really work. Already for helium they couldn't make sense of the spectrum without employing strange new ad-hoc assumptions. I think it's fair to say that they had to invent more such "quantum rules" for any sort of atom they looked at. Also the Stark effect (by the way solved by Schwarzschild in his last scientific paper of 1916 within the Bohr-Sommerfeld quantization) didn't work out right.

So for the atomic physicists of the time Heisenberg's and Schrödinger's "new quantum theory" (proven to be the same theory only written in different mathematical language as "matrix mechanics" or "wave mechanics", respectively) was a great relief since in an amazing pace the physicists of the time could show that this works (and it works till today!) without ad-hoc assumptions but right away for any atom (and any other matter around us, i.e., nuclei, molecules, condensed matter, and in its relativistic version also elementary particles up to the highest available energies at the LHC).