The micropolariry of the supercages of zeolites is a reflection of the electric field provided by the cations present within them. The notion of polarity within the cages of X and Y zeolite does not have precisely the same meaning as in solution. In this study, pyrene, pyrenealdehyde, and para‐dimethylaminobenzonitrile have been used as photophysical probes to monitor the polarity of the zeolite interior. With pyrenealdehyde and para‐dimethylaminobenzonitrile the supercage wherein the probe is expected to reside is more polar or possesses a higher electric field when the cation is Li or Na. The polarity/electric field of the supercage decreases with cation size (Li > Na > K > Rb > Cs) and the supercage is more polar in the case of X zeolites than in Y zeolites. The results with pyrene are generally consistent with those with the other two probes. However, pyrene is unable to sense the difference between Li. Na and other cations.
|Original language||English (US)|
|Number of pages||7|
|Journal||Photochemistry and Photobiology|
|State||Published - 1992|
ASJC Scopus subject areas
- Physical and Theoretical Chemistry