Nonadiabatic chemistry

Thermal Nonadiabatic Chemistry Involving Conical Intersections... 

Conical intersections are involved in other types of chemistry in addition to photochemistry. Photochemical reactions are nonadiabatic because they involve at least two potential energy surfaces, and decay from the excited state to the ground state takes place as shown, for example, in Figure 9.2a. However, there are also other types of nonadiabatic chemistry, which start on the ground state, followed by an ex-cnrsion npward onto the excited state (Fig. 9.2b). Electron transfer problems belong to this class of nonadiabatic chemistry, and we have documented conical intersection... 

THERMAL NONADIABATIC CHEMISTRY INVOLVING CONICAL INTERSECTIONS (ELECTRON TRANSFER)... 

We now turn to an example of nonadiabatic chemistry where the nonadiabatic process starts on the ground state, and is followed by an excursion upward onto the excited state electron transfer (see references 2-5). 

Yarkony DR (1996) Current issues in nonadiabatic chemistry. J Phys Chem 100 18612... 

D. R Yarkony, /. Phys. Chem., 100, 18612 (1996). Current Issues in Nonadiabatic Chemistry. 

After describing why there is a problem, I will briefly summarize the theoretical description of spin-forbidden reactions. It will be useful at this point to draw parallels with other types of nonadiabatic chemistry, in particular, electron transfer. Then I will review some of the typical contexts in which spin-forbidden behavior occurs in transition metal systems, to try to illustrate how widespread it is. This will be followed by a presentation of strategies used for characterizing and understanding spin-forbidden reactions, based on the use of energies and... 

Spin-forbidden reactions are a subset of the broader class of electronically non-adiabatic processes, which involve more than one PES. The fundamental theory of how such processes occur is well understood (7-9), and a very large amount of research is being performed with the aim of elucidating more details in all the areas of nonadiabatic chemistry. It is not possible to present this work here, so I will instead provide an outline of the most important theoretical insights in the... 

Potential Energy Surfaces for Ground-State Electron Transfer, Relation to Photochemistry Nonadiabatic Chemistry... 

To appropriately describe the quantum dynamics in such nonadiabatic chemistry in intense laser fields and highly degenerate states, a theory based on time-dependent nonadiabatic electron wavepackets is an essential requirement, which will be studied below in this chapter. 

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