SEPARATION OF MAGNETIC-FIELD EFFECTS ON THE PHOTOREDUCTION OF XANTHONE WITH P-AMINOTHIOPHENOL INTO THE EFFECTS DUE TO THE DELTA-G AND RELAXATION MECHANISMS

The inversion observed at 0.1 T for the magnetic field effects (MFEs) on the photoreduction of xanthone with p-aminothiophenol was investiga ted in the absence and the presence of a paramagnetic Gd3+ ion with th e aid of a laser flash photolysis technique. The MFEs owing to the Del ta g and relaxation mechanisms were experimentally separated by the ad dition of Gd3+. Thus, we have proved for the present reaction that the MFEs owing to the hyperfine coupling mechanism and relaxation mechani sm appear in a low field region (below 0.1 T) and that the MFEs owing to the Delta g mechanism gradually appear in a high field region (abov e 0.1 T).