Can you confirm the value of the g-factor for the spinning electron in H1?

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SUMMARY

The discussion centers on the gyromagnetic factor (g-factor) for the spinning electron in hydrogen (H1). The classical model calculations yield a mechanical orbital angular momentum (L) of 1.0546 x 10^-34 J*s and a magnetic moment (μ) of 9.274 x 10^-24 J/T, leading to a gyromagnetic ratio (γ) of 8.79 x 10^10 r/Ts. The discrepancy between the expected classical g-factor of 1 and the observed value of 2.0023 highlights the need for the g-factor to account for quantum effects. The classical radius of the electron does not factor into these calculations.

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bobie
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I am studying the angular moment(s) in an atom of H (1s) in the classical model, can you help me understand some obscure points :
The mechanical orbital angular moment of the electron in 1s is L = mvr J*s:

(m) 9.11*10-31 *(v) 2.1877*106* (r) .52918*10-10 = 1.0546*10-34 J*s = h/2π,

the magnetic moment is μ = qvr/2 J/T:
1.6*10-19*(v) 2.1877*106* (r) .52918*10-10 /2=9.274 *10-24 J/T

first problem : this is the exact value of Bohr magneton μB (= qh/22πm), not of μ

The gyromagnetic factor γ (http://en.wikipedia.org/wiki/Magnetogyric_ratio) is the ratio μ / L : γ = qvr/2 *mvr = q/m2 (J/T / J*s =1/s*T) = 1.7588*1011/2 radian/s*T, γ = 8.79*1010 r/Ts
For the spinning electron wiki says:
As mentioned above, in classical physics one would expect the g-factor to be ge=1 ...(whereas it is 2.0023..., γe = 1.76*1011: q/m 1.7588*ge/2= 1.01169)
second question: how do I verify g=1, shall I take into account the electron classical radius 2.81*10-15 m* 9.11*10-31 kg and what speed?
Thanks for your help
 
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What are you asking here? The definitions that you gave for L and μ are the classical definitions Using that definition the gyromagnetic ratio is just the charge to mass ratio (divided by 2). that relationship is not realized experimentally hence the need to define the g-factor that measures the discrepancy between the classical result and the observed value. The classical radius of the electron doesn't show up anywhere in either the classical or the quantum calculations.
 
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dauto said:
What are you asking here?

hence the need to define the g-factor
The classical radius of the electron doesn't show up anywhere in either the classical or the quantum calculations.
In the article I quoted there is :
γ which is the ratio of the orbital momenta μ / L in H1 ( L = 1/2π and μ =q/2m).

γe which is the ratio ofbetween the electron "spin" angular momentum Le= \pm1/2 h/2π = h/ 4π, and magnetic moment μe/Le
and ge, the g-factor , the experimental factor that multiplies the expected classical, theoretical value of ye by 2.0023, if I got it right

The value of L in γ is mvr, where r should be the radius of the orbit in H1, Bohr radius
Isn't it so?
 
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