Nuclear Magnetic Moments - Oxygen 15

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SUMMARY

The calculation of the nuclear magnetic moment for Oxygen-15 was initially incorrect due to the misapplication of the angular momentum coupling formula. The correct approach involves using the formula for the g-factor as \( g_J = g_l (1 + \frac{1}{2l + 1}) - g_s (\frac{1}{2l + 1}) \), where \( g_l = 0 \) for neutrons. This adjustment yields a g-factor of \( g_J = -0.63 \), resulting in a nuclear magnetic moment of approximately \( -0.63 \mu_N \), which aligns closely with the literature value of \( \pm 0.7189 \mu_N \) from the NIST database.

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BOAS
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Homework Statement


I am trying to calculate the nuclear magnetic moment for Oxygen 15 but my answer differs strongly from the value quoted in literature.

Homework Equations

The Attempt at a Solution


[/B]
##\mu_J = g_J \mu_N J##

This isotope of Oxygen has an unpaired Neutron with ##J = \frac{1}{2}##.

Calculating the nuclear g-factor for ##J = l + \frac{1}{2}##

##g_J = g_l (1 - \frac{1}{2J}) + g_s(\frac{1}{2J})##

For a neutron ##g_l = 0## and so in this case ##g_J = g_s = -3.82##

I therefore find that ##\mu_J = -1.91 \mu_N## which is significantly different from the value I find in the NIST table of ##\pm 0.7189 \mu_N##

http://nist.gov/data/PDFfiles/jpcrd85.pdf

Is my treatment too simplistic to get a decent prediction, or am I making a fundamental error?

Thanks for reading!
 
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BOAS said:

Homework Statement


I am trying to calculate the nuclear magnetic moment for Oxygen 15 but my answer differs strongly from the value quoted in literature.

Homework Equations

The Attempt at a Solution


[/B]
##\mu_J = g_J \mu_N J##

This isotope of Oxygen has an unpaired Neutron with ##J = \frac{1}{2}##.

Calculating the nuclear g-factor for ##J = l + \frac{1}{2}##

##g_J = g_l (1 - \frac{1}{2J}) + g_s(\frac{1}{2J})##

For a neutron ##g_l = 0## and so in this case ##g_J = g_s = -3.82##

I therefore find that ##\mu_J = -1.91 \mu_N## which is significantly different from the value I find in the NIST table of ##\pm 0.7189 \mu_N##

http://nist.gov/data/PDFfiles/jpcrd85.pdf

Is my treatment too simplistic to get a decent prediction, or am I making a fundamental error?

Thanks for reading!

I think I have found my mistake.

My case is for J = L - S, with L = 1.

My g-factor is therefore ##g_J = g_l (1 + \frac{1}{2l + 1}) - g_s (\frac{1}{2l + 1})##, with ##g_l = 0##

I find that ##g_J = -0.63 \mu_N## which is much closer to my expected value.

Sorry for posting prematurely.
 

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