reduction is observable with this sample, suggesting that the approach to ion-exchange equilibrium is slowed greatly by the presence of the porphyrin monolayer. This result is in accord with the cyclic voltammetric experiments and supports the assertion that the porphyrin is mediating all electron transfers to and from the encapsulated viologen ions.Conclusions. We have demonstrated that zeolite Y can be used to organize, via ion exchange and steric effects, electroactive molecules at an electrode surface. Cationic porphyrin molecules adsorb onto the zeolite in monolayer quantities, effectively sealing it against rapid exchange of viologen molecules contained within. This microstructuring gives rise to electrochemical charge trapping reactions, like those observed with macrostructured polymer film devices. The application of these molecular assemblies to artificial photosynthesis is presently being explored.

Layered phosphonate salts of divalent metal ions (Mg, Mn, Zn, Ca, Cd) are precipitated by combining aqueous solutions of a phosphonic acid and a soluble metal salt. In this way compounds in the series M(03C^72n+i)'H20 (

No abstract

Polydiacetylene‐based chemosensors are prepared by assembling liposomes of diacetylene monomers with terminal amine groups on an aldehyde‐modified glass substrate, and polymerizing them by irradiation with UV light. Incubation of the immobilized film sensor in a poly(acrylic acid) solution results in a color change from the original blue (solid line in Figure) to the red phase (broken line).