trans-Stilbene (
t-St) is incorporated as an intact molecule without solvent in the medium size channel ofnonacidic aluminum rich Na
6.6ZSM-5 zeolite with Na
6.6(SiO
2)
89.4(AlO
2)
6.6 formula per unit cell. The interactionbetween Na
+ cation and
t-St occurs through one phenyl group facially coordinated to the Na
+ cation near theO atoms binding Al atoms. The similarity between Raman spectra of
t-St in solution and occluded in Na
6.6ZSM-5 shows that the motion of
t-St in the channel approaches at room temperature the isotropic limitcharacteristic of a liquid. The laser UV (266 nm) photoionization generates a primary
t-St
+-electron pair asa fast phenomenon. These charge carriers exhibit lifetimes that extend over less than 1 h at room temperatureand disappear according to two parallel competitive ways: direct charge recombination and electron transfer.This subsequent electron-transfer takes place between the electron deficient radical cation (
t-St
+) and theelectron donor oxygen atom of the zeolite framework. The aluminum rich Na
6.6ZSM-5 zeolite hinders efficientlythe charge recombination and promotes the electron transfer to generate a very long electron-hole pair whichexceeds several hours at room temperature. A one laser Resonance Raman experiment using exciting lineswithin the contour of the unique three band visible absorption spectrum characterizes the ground state ast-St@ZSM-5
+-. The three UV bands at 512, 558, and 613 nm correspond to a vibrational progression of the1600 cm
-1 mode (C-C stretching) in the excited state. A two laser resonance Raman experiment characterizesthe excited-state as a
t-St
+@ZSM-5
- radical cation electron pair.