Barrier height electron-exchange

This behaviour is reminiscent of dynamical averaging seen in NMR spectroscopy, which is treated using a Bloch-equation analysis. Turner and coworkers were the first to use this type of analysis of dynamic infrared spectra to calculate rate constants and self-isomerisation barrier heights in the case of a turnstile -type exchange of CO ligands observed in trigonal bipyramidal [(q -diene)Fe(CO)3] complexes. In a similar fashion, rate constants for electron transfer in the ruthenium cluster dimers were calculated from the lineshapes of the (—1) states. As expected from the electrochemical data, the rate constant was fastest for the most electronically coupled dimer (1) and slowest for the... 

When immersed in an electrolyte, a semiconductor undergoes an exchange of electrons with the liquid at the interface to equalize the work functions of the two phases. The result is often a rectifying barrier between the semiconductor and liquid that has properties similar to a Schottky barrier. Like semiconductor-metal contacts, the barrier height can be fixed by the semiconductor surface state distribution, or, in the case of a low density of surface states, by the difference between the work functions of the bulk semiconductor and the liquid. Similarly, a reaction between the semiconductor surface and the eiectrolyte can produce a surface layer that fixes the barrier height. 

With the radical atom in a state, there is no electronically nonadiabatic route for vibrational relaxation. This is a simplifying feature, but the mechanism responsible for removal of HX+ by H or D atoms remains unclear, largely because of uncertainty over the barrier heights for the abstraction and exchange processes, i.e.. 

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