Ion migration pathways

Keywords Battery materials Bond valence site energy model Ion migration pathways Solid electrolytes... 

Volume fraction of percolating ion migration pathway clusters... 

Fils0 M0, Turner MJ, Gibbs GV, Adams S, Spackman MA, Iversen BB (2013) Visualizing Lithium-ion migration pathways in battery materials. Chemistry-A European Journal 19 15535-15544... 

Several aqueous systems should be considered in a similar manner. For example, in the selective removal of divalent cations from a saturated salt solution, the hydrated resin gives up a portion of its normal water content as it contacts the salt stream. In so doing, the particles shrink, and the inner pathways for ion migration become smaller. 

Fig. 4.30 Structure of /f -alumina (a) alternating spinel blocks and conduction planes (b) migration pathway of Na+ ions indicating paths of concerted motion.

A number of other groups have recently used modelling to study ion migration in ceria, Ce02. The reaction pathway for migration of oxygen vacancies in ceria has been studied using the PAW method with GGA + The results confirm the... 

Backvall has devised a catalytic method for the conversion of 1,3-dienes into their 1,4-diacetoxy-derivatives. Less than 3% 1,2-addition occurs. The reaction is carried out in acetic acid using manganese(IV) oxide, together with a small quantity of benzoquinone, as oxidizing agent. The catalyst is palladium(II) acetate in the presence of lithium acetate. Under these conditions, 1,3-cyclohexadiene affords irflns-l,4-diacetoxycyclohexene (path (b)). If a little lithium chloride is also added, coordination of the acetate ion to palladium is blocked by chloride, the better of the two ligands. This suppresses the cis-migration pathway (b) so that cis-1,4-diacetoxycyclohexene (path (a)) now becomes essentially the only product. If the concentration of lithium chloride is increased still further, chloride replaces acetate as the second nucleophile. 

Ingram MD, Mackenzie MA, Muller W et al (1988) Cluster and pathways a new approach to ion migration in glass. Solid State Ionics 28-30 677-680... 

Figure 29.2 Structure of -alumina showing (a) the altemation of spinei biocks and conduction planes (b)the honeycemb pathway along which Na ions migrate and the kind of concerted mechanism that is envisaged (Courtesy ef Chleride Silent Power)...

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