Tactoid concept

This has2been shown to be correct by using cis-Ru(bpy)2(H20)2 as catalyst then all the components for the reaction are within the interlamellar space and photooxidation proceeds at a rate comparable with that observed in solution (Figure 7c). These observations outline the importance of the textural arrangement of the clay sheets with respect to the availability of the surface sites, in line with what has been previously discussed in the paragraph dealing with the concept of tactoids. 

A bit of explanation is required here for those readers unfamiliar with the condensation concept, a key notion to describe polyelectrolytes. Consider as here a polyanion. If the charges are brought closer to one another, on the average, below a critical distance their mutual repulsion is such that — in order to continue to obey first principles electrostatics such as the Poisson equation — they screen themselves with an atmosphere of counterions. This atmospheric condensation, which can coexist with ionic binding at the individual sites, boosts the local concentration of counterions in the space surrounding the polyelectrolyte by as much as three orders of magnitude. The nmr measurements analyzed here focus on these water hydration molecules coordinated to condensed sodium counterions, next to the surface of the tactoids (see Fripiat s chapter). 

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