McConnell equation

McConnell equation describes the proportional dependence of the hyperfine splitting constant ${\displaystyle a}$ on the spin density ${\displaystyle \rho }$ (the probability of an unpaired electron being on a particular atom) in aromatic radical compounds such as benzene radical anion ${\displaystyle C_{6}H_{6}^{-}}$.

${\displaystyle a=Q\rho }$

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