# Gyromagnetic ratio

(Difference between revisions)
 Revision as of 21:54, 22 April 2009 (edit) (→References)← Previous diff Current revision (21:54, 22 April 2009) (edit) (undo) (→References) Line 75: Line 75: #nistval values are divided by 2*pi, those in nist tables are not #nistval values are divided by 2*pi, those in nist tables are not - #niste [http://physics.nist.gov/cgi-bin/cuu/Value?qgammae gyromagnetic ratio of free electron] + #niste [http://physics.nist.gov/cgi-bin/cuu/Value?eqgammae gyromagnetic ratio of free electron] [[Category:NMR concept]] [[Category:NMR concept]] [[Category:Fixme]] [[Category:Fixme]]

## Current revision

Gyromagnetic Ratio is defined by: $\gamma = \frac{e}{2m_p}g = g \mu_\mathrm{N}/\hbar,$

where $\displaystyle e$ is the magnitude of electron charge, $\displaystyle m_p$ is the proton mass, $\displaystyle \hbar$ is reduced Planck constant, $\displaystyle \mu_\mathrm{N}$ is the nuclear magneton, and $\displaystyle g$ is the g-factor of the nucleon or nucleus in question.

Approximate values for some common nuclei are given in the Table below.<ref>Template:Cite book</ref>

species γ / 2π (MHz/T) 
free electron 2.80249536 x 104 
1H 42.576
2D 6.53593
3He -32.434
7Li 16.546
13C 10.705
14N 3.0766
15N -4.3156
17O -5.7716
19F 40.0593
23Na 11.262
31P 17.235
75As 7.2919
129Xe -11.777

For information on individual chemical elements please use NMR and EPR Periodic Table

To find NMR frequency of your favorite nucleus at a given magnetic field, see Alex Jerschow's on-line Interactive NMR Frequency Map

## References

1. values are divided by 2*pi, those in nist tables are not [nistval]
2. gyromagnetic ratio of free electron [niste]