H-1, C-13 and O-17 isotropic and anisotropic hyperfine coupling prediction for the tyrosyl radical using hybrid density functional methods

Hybrid density functional calculations are used to directly calculate the principal hyperfine tensor values for H-1, C-13 and O-17 in two models of the tyrosyl radical, p-methylphenoxyl and p-ethylphenoxyl. Both hydrogen bonded and non-hydrogen bonded phenoxyl radicals are studied. A comparison is made between calculated values and those obtained from experimental EPR and ENDOR studies. Outstanding agreement between experiment and theory is observed.