McConnell equation explained

C _{6H} ^{-} ^{6} ) being on a particular atom. It relates this probability, known as the "spin density", to its proportional dependence on the hyperfine splitting constant.

The equation is$$a\; =\; Q\; \backslash rho,$$where $a$ is the hyperfine splitting constant, $\backslash rho$ is the spin density, and $Q$ is an empirical constant that can range from 2.0 to 2.5 mT.

History

The equation is named after Harden M. McConnell of Stanford University, who first presented it in 1956.^[1]

References

• Book: Atkins . Peter . Peter Atkins . de Paula . Julio . Atkins' Physical Chemistry . 9th . Oxford University Press.

Notes and References

1. McConell . H. M. . 1956 . Indirect Hyperfine Interactions in the Paramagnetic Resonance Spectra of Aromatic Free Radicals . . 24 . 764–766 . 10.1063/1.1742605.