Study of Triplet—Triplet Transfer by the Method of Magnetophotoselection. II. Concentration Depolarization

Publisher Website
Google Scholar
Abstract
The concentration depolarization of the spectra from Δm=±1 electron paramagnetic resonance (EPR) transitions of photoexcited naphthalene‐d8 triplet‐state molecules dissolved in ethanol glasses at 77°K has been studied. An analysis of the results is made in terms of triplet‐state energy transfer. It is shown that the results are completely consistent with an electron exchange triplet‐state energy‐transfer mechanism, with the probability of transfer being the same as that found in the case of transfer between unlike molecules. However, for the self‐transfer case, back transfer is important and it was included in the analysis. It was also necessary to assume in the theoretical analysis that the rate of transfer between molecules at the effective transfer distance is slow compared to the rate of relaxation of the spin magnetization. Some preliminary evidence is presented for an appreciable solvent effect on the polarization of the 1La band of naphthalene.