OSCILLATING MAGNETIC-FIELD EFFECTS ON THE YIELDS OF RADICAL PAIR REACTIONS

The effects of fluctuating magnetic fields on the yields of chemical r eactions are explored within the radical pair mechanism, for the case in which singlet and triplet radical pairs disappear at equal rates. A pproximate analytical expressions and exact numerical calculations are used to discuss the origin of the oscillating magnetic field effect ( OMFE), its likely magnitude, and its dependence on radical pair lifeti me, magnetic field strength and frequency. Changes in product yields o f up to 25% are predicted for fields at frequencies corresponding to h yperfine splittings (1-100 MHz) in the radicals. The largest effects a re expected when the singlet-triplet interconversion induced by the os cillating field is much faster than the rate of reaction of the radica l pair, The likelihood of observing the OMFE experimentally is discuss ed.