Zeolite is a porous highly interactive matrix. Zeolitic cations help to generate triplets from molecules that possess poor intersystem crossing efficiency. Certain zeolites act as electron acceptors and thus can spontaneously generate radical cations. Zeolites also act as proton donors and thus yield carbocations without any additional reagents. These reactive species, radical cations and carbocations, have long lifetime within a zeolite and thus lend themseleves to be handled as ‘regular’ chemicals. Internal structure of zeolites is studded with cations, the counter-ions of the anionic framework. The internal constrained structure and the cations serve as handles for
chemists to control the behavior of guest molecules included within zeolites.