Diabatic constraint, defined

A manner to do away with the problem is to introduce appropriate algorithms in the sense that mappings from real space to Hilbert space can be defined. The generalized electronic diabatic, GED approach fulfils this constraint while the BO scheme as given by Meyer [2] does not due to an early introduction of center-of-mass coordinates and rotating frame. The standard BO takes a typical molecule as an object description. Similarly, the wave function is taken to describe the electrons and nuclei. Thus, the adiabatic picture follows. The electrons instantaneously follow the position of the nuclei. This picture requires the system to be always in the ground state. 

It is desirable to have a means of defining diabatic states (V i and V r) and Tfjf which is free of the constraint of D/A resonance, e.g., in the case of optical ET where one may obtain estimates of H[ to be compared with corresponding values inferred from thermal kinetics, and which may be of value in predicting thermal kinetics when thermal estimates are not available. ... 

The purpose of the cDFT approach is to define diabatic states that resemble as much as possible the phenomenological Marcus states. To this end, a Lagrange multiplier technique is employed to apply a constraint on the charge distribution within the supramolecule. In the case of an electron transfer reaction, an adequate functional F subjected to minimization is written as ... 

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