Temperature-dependent electron tunneling. Methods of determining the activation energy

Along with the temperature-independent electron tunneling reactions, there exist reactions of the type for which the rate depends on temperature. In the present section we shall discuss the methods of determining the activation energy for those processes from their kinetic curves. 

In Chap. 3, it was shown that the activation energy of electron tunneling reactions diminishes with decrease in temperature. Let us consider the temperature interval in which the activation energy can be considered to be approximately constant. Then, the probability of electron tunneling can be represented as 

In eqn. (23) voe is the pre-exponential factor which only weakly depends on temperature and En is the activation energy. 

The most natural method of determining the activation energy of the 

Experimentally, the decay of the reagents at temperature T in the samples, which have initially been kept for some time, ta, at another temperature, T0 T, is often studied. In this case, the distance of tunneling, Rt, which for lF(i ) of eqn. (22) obeys, by definition, the relationship VE(i t) t = 1, can be calculated for the times t t0 from the ratio 

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