The transferred hyperfine interaction has been investigated in Co2P2O7 by means of the 31P nuclear magnetic resonance. The expectation values of the cobalt ion spins were determined from the electron spin resonance of Co++ ions in the isomorphous diamagnetic salt Mg2P2O7. The values were confirmed by comparison with bulk susceptibility measurements. The fraction of unpaired electron transferred per Co–O–P path is (0.057 ± 0.005)%. This value is anomalously small compared with previous results of the transferred hyperfine interaction in Mn2P2O7.
AbstractThe width of the first Hfs-line of the Mn++ EPR-spectrum in aqueous solutions with added diamagnetic and paramagnetic iron group or rare earth ions was measured at 3 cm wavelength and at 300 °K. The difference ΔHD in linewidth of Mn++ in the paramagnetic and diamagnetic salt solutions is ascribed to dipolar interaction between Mn++ and the other paramagnetic ions e. g. Co++ , Ni++ and Ce3+ . The relaxation times τs of these ions are too short for the EPR-spectrum to be detected in liquids. From the excess linewidth ΔHD relaxation times Ts for Co++ , Ni++ and Ce3+ are estimated which agree well with τs results from proton relaxation measurements in paramagnetic salt solutions.
Indirekte Bestimmung kurzer Relaxationszeiten von paramagnetischen Ionen in wäßriger Lösung