engleski

Dynamics of stable paramagnetic centers in L-alanine studied by transfer saturation EPR

The stable l-alanine radical was examined by transfer saturation EPR (CW-TSEPR) in the temperature region of fast motion of the methyl group (180 K-320 K). From the obtained spectral line broadening and saturation factors of the spectral intensities it was demonstrated that relaxation rate strongly depends on spectral diffusion mechanism. The temperature dependence of the saturation behavior of CW-TSEPR spectra have been analyzed. It was noted that besides correlation time of the methyl group of stable radical center an additional correlation time should be involved in the relaxation process. This additional correlation time originated from the neighbor methyl groups of the radical centers. The obtained dynamical parameters have been compared with those previously obtained by proton nuclear magnetic resonance (NMR) on undamaged crystals.

alanine; dosimetry; ESR

nije evidentirano