# Larmor Frequency spin, orbital or total angular momentum?

#### Master J

Larmor Frequency...spin, orbital or total angular momentum??

For an electron bound in an atom, its orbital angular momentum L precesses around the magnetic field applied B, at the Larmor Frequency...or is it that its TOTAL L precesses around
B, while L precesses around this, and its spin angular momentum around L?? Are these precessions all at the same Larmor Frequency??

For a FREE electron, in a magnetic field, will its SPIN angular momentum do the same,that is, precess around B, also at the Larmor Frequency?

I am a bit confused as I have seen the precession and Larmor Frequency refer to all of the above cases.

Hope someone can clear this up.

Thanks!

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#### DrClaude

Mentor
It is the total angular momentum $J$ of the electron that will precess around B.

"Larmor Frequency spin, orbital or total angular momentum?"

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