Electrode parent atom

We shall be concerned primarily with the behavior of ionic charge carriers at the interface, and the electrode-electrolyte combinations to be encountered will fall into two general groups parent-atom electrodes and redox electrodes. In parent-atom electrodes, charge can cross the interface in ionic form. Electrodes of this type include parent-metal electrodes such as Ag in the solid state cell Ag AgCl Ag, in which the electrode serves both as a source of ions and as an electronic conductor, and parent-nonmetal electrodes, as in the cell Br2(Pt) AgBr Br2(Pt), in which an inert metal phase must be present to serve as the electronic conductor. In redox electrodes. 

Electrochemical oxidation of silatranes in carefully dried MeCN on a glassy carbon electrode was shown280,281 to be a diffusional process which proceeds with one-electron transfer. At room temperature electrooxidation is reversible at scan rates below 100 mV s-1 and is partially reversible at higher scan rates (200, 500 mV s 1) but becomes reversible at low temperatures (< —10 °C). It was suggested that the primary products are cation radicals 54 of relatively low stability in which the distance between the silicon and nitrogen atom is higher than in the parent molecules (equation 54). 

Virtually all recent quantitative investigations of atom reactions in discharge-flow systems have employed either a microwave or radio-frequency discharge in the parent molecules as the source of atoms. The use of a 50 Hz discharge at several kV potential between a pair of metal electrodes in contact with the gas flow has been superseded by these convenient so-called electrodeless discharges. The absence... 

The element Z e is a general diffusion impedance added to account for possible diffusion of uncharged reactants such as oxygen atoms (but not parent-electrode atoms) in the electrodes (for the present full-cell situation it accounts, of course, for diffusion in both electrodes). When p = 0 it should not appear. In most cases of... 

For reactions of this kind to occur, it is necessary that the parent compound should be reducible at an accessible electrode potential, i.e., that it should have a sufficiently high electron affinity. Olefins cannot be reduced in this way and even 1,3-dienes are marginal. Since replacement of a carbon atom in a conjugated system lowers the energies of all the MOs (except those with nodes at the atom in question), hetero-analogs of dienes are, on the other hand, easily reduced (e.g., CH2=CH—CR=0, CH2=CH—C=N). 

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