Wednesday, November 10, 2010
Adiabatic, non-adiabatic, or diabatic?
The Diabatic Picture of Electron Transfer, Reaction Barriers, and Molecular Dynamics. This is the review article that we will be discussing at the cake meeting tomorrow. It is clear and helpful.
Adiabatic states are the eigenstates of the electronic Schrodinger equation in the Born-Oppenheimer approximation. There are several problems with them
-they can vary significantly in character with changes in nuclear geometry [in particular they can be singular near conical intersections]
-they are not a good starting point for describing non-adiabatic processes such as transitions between potential energy surface
-they are hard to connect to chemical intuitive concepts such as valence bond and ionic states
Diabatic states overcome some of these problems. They do not vary significantly with changes in nuclear geometry.
However, determining them is non-trivial. The article describes these issues.