Why is the s state spherically symmetric?

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SUMMARY

The discussion centers on the s state of electrons in quantum mechanics, specifically in the context of the Schrödinger equation for the Hydrogen atom. When the principal quantum number n=4, the s state, characterized by the quantum number ℓ=0, is described as spherically symmetric due to the absence of angular momentum. Although initial references suggest a flattened elliptical shape, this is a remnant of the Bohr-Sommerfeld model, while the true quantum mechanical interpretation reveals that the probability distribution of the electron's position is spherically symmetric.

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This discussion is beneficial for physics students, educators, and anyone interested in deepening their understanding of quantum mechanics and atomic structure, particularly in relation to electron behavior and orbital shapes.

KFC
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Hi there,
I am reading something about quantum numbers, there the author introduce the quantum number by solving Schrödinger equation for Hydrogen atom. It gives me an example when the principal quantum number n=4, there are four different sub-level ##s, p, d, f##. It also depicts the sublevel for them. It is said that for s state which ##\ell=0##, the shape is something like a completely flattened ellipse going through the nucleus. But since ##\ell=0##, there is no angular momentum, the electron is not "orbiting" anything; hence, it must be totally radially so s state is spherically symmetric.

It is quite confusing for me. Since it is said at the beginning it is flatten ellipse but later becomes spherically symmetric.

reference: http://web.pdx.edu/~pmoeck/lectures/312/chapter 7 part 3.doc
page 3 and page 8
 
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KFC said:
It is said that for s state which ##\ell=0##, the shape is something like a completely flattened ellipse going through the nucleus.
Where does your reference say that?
KFC said:
But since ##\ell=0##, there is no angular momentum, the electron is not "orbiting" anything; hence, it must be totally radially so s state is spherically symmetric.
Right. s orbitals are spherically symmetric.
 
Doc Al said:
Where does your reference say that?

Right. s orbitals are spherically symmetric.

Sorry that I give the wrong reference. I just get it corrected. And in the document given by the link, in page 3, note below the caption of FIGURE 7.3, it is said that "for l=0 we have a completely flattened ellipse that goes through the nucleus, this will be later called an s state."
 
Those elliptical orbits are remnants of the Bohr-Sommerfeld model of the atom. (Old stuff!) Note the diagram on page 20 of your reference, which shows the s orbitals as spherical.
 
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Thanks a lot.
 
KFC said:
Hi there,
I am reading something about quantum numbers, there the author introduce the quantum number by solving Schrödinger equation for Hydrogen atom. It gives me an example when the principal quantum number n=4, there are four different sub-level ##s, p, d, f##. It also depicts the sublevel for them. It is said that for s state which ##\ell=0##, the shape is something like a completely flattened ellipse going through the nucleus. But since ##\ell=0##, there is no angular momentum, the electron is not "orbiting" anything; hence, it must be totally radially so s state is spherically symmetric.

It is quite confusing for me. Since it is said at the beginning it is flatten ellipse but later becomes spherically symmetric.

reference: http://web.pdx.edu/~pmoeck/lectures/312/chapter 7 part 3.doc
page 3 and page 8
According to my prejudices, I always warn against physics manuscripts written with Word. This one cements my prejudice. SCNR.
 
Classically, an orbit with l=0 corresponds to the electron falling straight on or through the nucleus. Quantum mechanically, the orientation of this line becomes completely undetermined.
 
Quantum mechanically ##l=0## means that your wave function and thus the probability distribution for the particle's position (and momentum) is spherically symmetric.
 

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