Polaron coupling constant

It will be useful to express the self-energy of the polaron in the two models in units of a dimensionless coupling constant which is considerably important in polaron theory ... 

The e-mv coupling constants ga characterize the molecule while the dimensionless e-mv coupling constants a describe all molecular stacks. This is why the ga values determined for various ion-radical salts of the same donor (or acceptor) molecule are close to one another. Thus the average values of ga can be calculated and compared with ga values calculated using a quantum chemistry method [50]. Mean values of ga for about 20 TCNQ salts are collected in Table 1. From these data one can evaluate the energy of polaron formation ... 

In fact, there is no qualitative difference between the IT polaron and the Holstein polaron in this region. Even quantitatively, they are exactly the same, as long as the coupling constants are normalized according to (24). 

In the small polaron theory the coupling constant St is much greater than 1, which allows the calculation of integrals in expression (219) [165]... 

As discussed by Travers [102], this can be due to either (1) an increase in the intrachain diffusion rate or (2) a decrease in the electron-proton coupling constants. In case 1, hydration has an effect on the polaron mobility, i.e., the latter is enhanced in case 2, hydration modifies the polaron electronic wave function. In addition, T p shows that the low frequency contribution to the proton relaxation is not affected, which is not consistent with a change in the coupling constant. It can be concluded that the increase in the macroscopic conductivity observed on hydration is related to an increase of the on-chain polaron mobility. A possible explanation can be proposed in terms of a solvation effect of the counterions resulting in a depinning of the polarons. 

The vibronic constants Va and Vb represent the coupling between Ajg (Big) with the displacements aig (big), respectively, and A is the energy splitting between electronic levels, while Qt=a,b stands for the symmetric nuclear displacements. For i = 1,2,... n JT centers surrounding a polaron, the Hamiltonian is. 

An analysis conducted in Ref. 165 has shown that the phonon-phonon interaction that is described by the constant % does not virtually influence St,i However, the interaction leads to a considerable coupling of a polaron with... 

Interfacial Polaron Limit In the absence of a barrier in the electrochemical potential of the ion, the rate constant for ion transfer is controlled by a two-dimensional diffusion of the ion and an interfacial protrusion, and is determined by an effective diffusion coefficient, for the ion-protrusion couple. 

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