Landau-Zener quantum tunnelling

Figure 7. Detail of the energy level diagram near an avoided level crossing, m and m are the quantum numbers of the energy level. Pm m- is the Landau-Zener tunnel probability when sweeping the applied field from the left to the right over the anticrossing. The greater the gap A and the slower the sweeping rate, the higher is the tunnel rate, Eq. (2).

It can then be calculated by using the Landau-Zener theory as discussed in Sec.6.1.II. In general, however, nuclear motion should be treated quantum-mechanically hence, the tunneling of solvent molecules must be taken into account, as done in the considerations in Sec.6.2 II. The reaction probability, i.e., the probability of an electron... 

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