Absolute values for the rate constants for intersystem crossing to each of the triplet sublevels have been determined. This has been achieved by monitoring both the phosphorescence and the fluorescence in an optically detected magnetic resonance experiment. Using the above absolute values togethr with the measured value for the phosphorescence quantum yield allows us to determine the absolute values for the radiative and nonradiative rate constants for decay from the individual sublevels of the triplet state.(AIP)

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