MAGNETIC-FIELD EFFECT IN CH3F NUCLEAR-SPIN CONVERSION

We predict the influence of an external homogeneous magnetic field on nuclear spin conversion in molecules. The effect arises either from th e Zeeman splittings or from the magnetic shielding of the molecular nu clei. The magnitude of the effects in CH,F molecules is estimated. The Zeeman effect call be large. The shielding effect is found to be rela tively small at reasonable magnetic fields, but it is shown that the m agnitude of the effect can be enhanced by using an alternating magneti c field at a resonant frequency. (C) 1997 Published by Elsevier Scienc e B.V.