Electrostatic energy, transferring electron

In the crudest approximation, the effect of the efectrical double layer on electron transfer is taken into account by introduction of the electrostatic energy -e /i of the electron in the acceptor into the free energy of the transition AF [Frumkin correction see Eq. (34.25)], so that corrected Tafel plots are obtained in the coordinates In i vs. e(E - /i). Here /i is the average electric potential at the site of location of the acceptor ion. It depends on the concentration of supporting electrolyte and is small at large concentrations. Such approach implies in fact that the reacting ion represents a probe ion (i.e., it does not disturb the electric held distribution). 

Coulombic energy transfer is a consequence of mutual electrostatic repulsion between the electrons of the donor and acceptor molecules. As D relaxes to D, the transition dipole thus created interacts by Coulombic (electrostatic) repulsion with the transition dipole created by the simultaneous electronic excitation of A to A (Figure 6.9). 

In electrochemistry, we deal with the energy level of charged particles such as electrons and ions in condensed phases. The electrochemical potential, Pi,of a charged particle i in a condensed phase is defined by the differential work done for the charged particle to transfer from the standard reference level (e.g. the standard gaseous state) at infinity = 0) to the interior of the condensed phase. The electrochemical potential may be conventionally divided into two terms the chemical potential Pi and the electrostatic energy Zi e as shown in Eqn. 1-21 ... 

Figures 4-11 and 4-12 show schematic energy diagrams for the electron transfer from the standard gaseous state through the electrolyte solution into the metal electrode. As mentioned in Chap. 2, the electron level (the real potential of electron) a s/v> in an electrolyte solution consists of an electrostatic energy...

To obtain a complete picture of bonding in acid-base interactions, three separate factors must be taken into account a) the electrostatic energy of the acid-base interaction b) the covalent energy of the acid-base interaction c) the energy involved when electron transfer takes place. These results were anticipated in principle on the basis of Mulliken-Jaffe electronegativity.37... 

These are produced by autoionization transitions from highly excited atoms with an inner vacancy. In many cases it is the main process of spontaneous de-excitation of atoms with a vacancy. Let us recall that the wave function of the autoionizing state (33.1) is the superposition of wave functions of discrete and continuous spectra. Mixing of discrete state with continuum is conditioned by the matrix element of the Hamiltonian (actually, of electrostatic interaction between electrons) with respect to these functions. One electron fills in the vacancy, whereas the energy (in the form of a virtual photon) of its transition is transferred by the above mentioned interaction to the other electron, which leaves the atom as a free Auger electron. Its energy a equals the difference in the energies of the ion in initial and final states ... 

A notable exception are chemisorbed complexes in zeolites, which have been characterized both structurally and spectroscopically, and for which the interpretation of electronic spectra has met with a considerable success. The reason for the former is the well-defined, although complex, structure of the zeolite framework in which the cations are distributed among a few types of available sites the fortunate circumstance of the latter is that the interaction between the cations, which act as selective chemisorption centers, and the zeolite framework is primarily only electrostatic. The theory that applies for this case is the ligand field theory of the ion-molecule complexes usually placed in trigonal fields of the zeolite cation sites (29). Quantum mechanical exchange interactions with the zeolite framework are justifiably neglected except for very small effects in resonance energy transfer (J30). ... 

The situation changes sharply the moment the receptor module within the molecular system captures the chosen analyte (which is a cation for the purposes of illustration). Again, if we consider excitation of the lumophore module, we find the analyte influences the transferring electron. At the simplest level, this is due to electrostatic charge attraction between the jumping electron and the captured analyte. So the photoinduced electron transfer is arrested and the unused energy of the excited state is dumped as a luminescence photon. This is how the analyte population is visualized. Now we have the on state of the molecular switch. 

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