Charge-compensated ion

These conjugated polymers can be chemically and electrochemically reduced and reoxidized in a reversible manner. In all cases the charges on the polymer backbone must be compensated by ions from the reaction medium which are then incorporated into the polymer lattice. The rate of the doping process is dependent on the mobiHty of these charge compensating ions into and out of the polymer matrix. 

It was reabzed early on that because of their high electron transport rates, the charging rates of conducting polymer films would be controlled predominantly by the rate at which charge-compensating ions [Eq.(l)] could be extracted from, or ejected into, the bathing electrolyte solution.160,161 However, these and some other studies employing chronoam-... 

The shape selectivity of zeolites is influenced by the location and distribution of charge-compensating cations. The charge-compensating ions other than protons are all quadrupolar. and Li NMR spectra of dehydrated LiX-1.0 identified three crystallographically distinct sites [221]. In the case NaX with Si/Al ratio of 1.23, six distinct sodium sites were identified using fast Na NMR, DOR and nutation techniques [222]. Na MQMAS has been extensively studied for zeolites X and Y [155]. Other cations like Cs and La in zeolites have also been investigated [155,... 

The data in the first frame are the (normalised) current, representing the electron flux. In the second frame, the overall mass flux (transfer of charge-compensating ions as well as neutral species) is shown. The third frame corresponds to the difference between the first two. The quantity defined by equation [3] with tm = 99.5 g mol"1 and Z = -1, represents the flux of all species other than perchlorate. In the case of the dilute (concentrated) electrolyte, this corresponds to the mass flux of water (water+salt). 

For samples A-C the lower values of Na/Al indicate the presence of hydronium ions as charge compensating ions. The samples were crystalline and all the lines could be indexed assuming the structure of Linde NaY (Sample A). The high crystallinity of these samples is also borne out by their similar values for the adsorption of H 0 and benzene (30.3 29.3 29.3 and... 

In light of the work of Ure (23) showing the conductivity of calcium fluoride being mainly caused by the motion of fluoride ion, the solid state reduction reactions have been interpreted in terms of a model which allows reduction to occur by diffusion of the interstitial, charge compensating ion out of the crystal while an electron is injected to reduce the trivalent lanthanide. Under these conditions there is no hole or electron deficiency remaining in the crystal, as in the case of radiation reduction hence the divalent species is stable. 

Trivalent rare earth or actinide ions can be incorporated in the alkaline earth halides in sites of various symmetries. Since the crystal as a whole must be electrically neutral, charge-compensating ions must also... 

Nevertheless, there are many cases where charge-compensation cannot be effected, in spite of anything we might try to do, A case in point is CaF2 Dy3+. We might try to use Na+ as a charge-compensating ion, but we... 

Even if all oxygen atoms are excluded during the reaction to form the crystal (including that of water), lattice defects will be formed. In fact, the presence of charge-compensating ions do not affect these defect reactions. The phosphor compositions we obtain because of the predominance of the defect reactions are ... 

The linear branches of the curve shown in Fig.7 are most likely due to diffusion of charge compensating ions in a film of restricted thickness. The large semicircle is characterized by the domination of the C2 and R2 components while the small semicircle (not always present) is usually accounted for by the Ci and Ri components, but the physical meaning of this is still ambiguous. The interpretation of the data has been discussed in more detail elsewhere. 

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