Comment on the Temperature Dependence of Radiationless Transition

As a further illustration of the general formalism developed in Chapter 3, we discuss the dependence of radiationless transition on temperature. One can distinguish clearly in Equations 3.75 and 3.77 between two contributions (of difference sources) to the temperature dependence. The dominant effect is given by the coth factor associated with the promoting modes. The second contribution is associated with the large number of accepting modes. At T = 0, all values in Equation 3.77 have to be 

Xexc = 633 nm. The spectra of Rb2TeCl6 Re(IV), revealing peaks determined by the CDs, CO4, CO3 bands (fundamentals) ofodd parity 

Let us now suppose for the sake of simplicity that the transition induced by the three odd parity modes is accompanied by a total symmetric accepting mode of frequency Q) (a = s, 0). This is the situation that most often occurs in a series of spectra of transitionmetal ions thathavebeeninvestigated bythe presentauthor (see, forexample. Ref. [100]). In this case, the overall line shape (see Equation 7.20b) is described by 

2) We are restating here conclusions obtained Chapter 4.6 about the temperature dependence of 

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