 When ω2 is the dominant relaxation process, a positive NOE results.This expression shows that for the homonuclear case where "I" = "S", most notably for 1"H" NMR, the maximum NOE that can be observed is 1\2 irrespective of the proximity of the nuclei.In the heteronuclear case where "I" ≠ "S", the maximum NOE is given by 1\2 ("γ"S/"γ"I), which, when observing heteronuclei under conditions of broadband proton decoupling, can produce major sensitivity improvements.