Quantum Mechanical systems considered in old QM

[wizrdofvortex]

Hello,

I know that blackbody radiation was one phenomenon whose study contributed to the conceptual development of QM early on. My first question is, what other such systems were considered?
I want to know this because I'm closely following the actual order of development of QM concepts, the way it was historically.

My second query is what systems were these theoretical ideas APPLIED to and successfully explained, in order for them (ideas) to gain acceptance?

Thanks in advance

 

[henry_m]

Hi,
Here's a couple of ideas:
Photoelectric effect.
The atom (treatments by Bohr and later Schroedinger); spectral lines and chemistry.
Wave nature of matter: electron diffraction, quantum double slit.
Stern-Gerlach

 

[Bill_K]

Einstein's treatment of the specific heat of a crystal lattice.

 

[wizrdofvortex]

Thanks... I'll take a look

 

[SpectraCat]

Hi,
Here's a couple of ideas:
Photoelectric effect.
The atom (treatments by Bohr and later Schroedinger); spectral lines and chemistry.
Wave nature of matter: electron diffraction, quantum double slit.
Stern-Gerlach

Actually, the original explanation of the Stern-Gerlach experiment in "Old QM theory" was incorrect. They didn't know about electron spin yet, so they thought the unpaired electrons would give silver atoms an orbital angular momentum of 1 ... (in fact, they have an orbital angular momentum of 0). In modern QM, an angular momentum of 1 should interact with a magnetic field gradient to give 3 bands, instead of the two that Stern & Gerlach observed. However, by a lucky coincidence, the Bohr-Sommerfield of angular momentum was ALSO incorrect, and predicted only two bands for an angular momentum of 1. So http://www.ru.nl/publish/pages/555655/3.jpg" for the full story. It took Goudsmit & Uhlenbeck to propose that electrons had an intrinsic angular momentum (spin), before the proper explanation for the original Stern Gerlach experiment was realized.

 

[wizrdofvortex]

Hello again,

I want to narrow down the question a bit... early on, as part of old QM, various systems would be analyzed via CLASSICAL mechanics, and then some quantization rules/selection rules would be applied to them, thereby obtaining a quantized set of energies, etc.

So any idea as to what these systems were? Of course, hydrogen atom is one example, as shown by Bohr, but I'm curious as to what other systems were considered besides H atom.