Electron-test-charge dielectric

Therefore, the electron-test-charge dielectric matrix is given by ... 

The test-charge-test-charge dielectric matrix is readily found if one inserts this expression for the exchange and correlation potential in the defining equation (Eq. 45) for the electron-test-charge dielectric matrix ... 

The test-charge-test-charge dielectric matrix allows to calculate the potential, due to a perturbation, as seen e.g. by the ions in the system. (The perturbation itself might be due to motions of the ions, since the ions are external in relation to the electron system.)... 

Another example of a process in which a charge is moved across an interface is interfacial electron transfer reactions. As in the case of ion transfer, experimental data on electron transfer across liquid-liquid interfaces are very limited. For this process, however, there exists a theoretical framework developed within a dielectric continuum model,which built on the fundamental theory of electron transfer in bulk media. Computer simulations, which complement experiments and theory, have not yet dealt with chemically realistic systems but, instead, considered idealized molecules to test the basic assumptions of the continuum model. 

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