For phenanthrene, the measured lifetime of the triplet state ( p ) is 3.3 s, the fluorescence

For phenanthrene, the measured lifetime of the triplet state (τ _p) is 3.3 s, the fluorescence quantum yield is 0.12, and the phosphorescence quantum yield is 0.13 in an alcohol–ether glass at 77 K. Assume that no quenching and no internal conversion from the singlet state occurs. Determine k _p, k ^T _isc, and k ^S _isc / k _f.