PHOSPHORESCENCE AND PHOTOCHEMICAL PROPERTIES OF BENZOPHENONE INCLUDEDWITHIN ALKALI-METAL CATION-EXCHANGED ZSM-5 ZEOLITES

The phosphorescence properties of benzophenone included within alkali metal cation-exchanged ZSM-5 zeolites were investigated to clarify the effects of the micro-environment of host-adsorbents on the electronic excited states of guest-molecules included within the restricted void spaces. Benzophenone included within such cation-exchanged ZSM-5 zeol ites was found to exist in both a protonated and hydrogen-bonded form. It was found that exchanging the cations dramatically affects the rat io of their contents. Photolysis of these systems revealed that both b enzhydrol and benzpinacol were the main products, their yields strongl y depending on the kind of the cations exchanged. Especially, the prot onated species was found to play a significant role in the photoreacti ons observed with benzophenone included within zeolite cavities.