Energy Transfer in the Excited Triplet State

Singlet energy transfer can be explained on the basis of coulombic interactions between 

Path length of light depend not depend not depend 

The generalized form of the transition probability for triplet-triplet energy transfer (Eq. (1.157)) was derived by Dexter, based on Eq. (1.156), where p3(v) is the phosphorescence spectrum and ebST(v) is the singlet-triplet absorption spectrum. 

Here again we forgo a detailed derivation of the equations, but outline only the general approach, so that at least the reader becomes familiar with the conceptual approach. 

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