Analysis of electron dynamics

Evolution of the unpaired electron distribution Panel (d) of Fig. 7.30 dynamically tracks the positions of the radical center in this spin singlet state. The total munber of the unpaired electrons is initially about 3.0 residing on PhO site before the first excited state passes across the conical intersection. After the passage, we see one on PhO and another on AMC mainly on AMI (before t = 130 fs). Again no radical center is created on the shifting proton nucleus. 

To further convince that this situation does not represent hydrogen-atom migration, we below show a typical example of such migration in a singlet excited state dynamics, in the first excited state dynamics of 

Returning to the phenol ammonia system, we next show in Fig. 7.33 how the spatial distribution of the unpaired electrons evolves in time. Before the first transition (see panel (a)) the unpaired electrons are distributed on the benzene ring and the oxygen atom. After the first transition (panel (b)), some large part of the unpaired electron density moves to AMI. At time 211 fs (after the second nonadiabatic transition, panel (d)), a large component of the unpaired electron is found on AM2, through a transient state at 148 fs (panel (c)). 

Chemical Theory Beyond the Born-Oppenheimer Paradigm. 

Electron flux suggesting an independent path of electron We 

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