Dynamic nuclear polarization and relaxation mechanism in some nitroxide free radical solutions

In this study the solutions of TANOL in water and oil at various concentrations and also the solutions of 4-Isothiocyanato-TEMPO in benzene were investigated in weak field region (1.53mT) using Dynamic Nuclear Polarization technique. The spectra of the samples were recorded. the extrapolated enhancements were obtained at each resonance frequency by the use of continuous wave saturation technique. The experimental and theoretical spectra were simulated using two different methods and from the values of the areas under the resonance curves the electronic relaxation times at each resonance frequency were determined. The obtained results were discussed and compared with the results in the other sources