Optical properties of chalcogen-loaded zeolite (ZSM-5)
نویسندگان
چکیده
Sulfur, selenium, and tellurium were loaded into sub-mm size ZSM-5 single crystals and the optical properties have been comparatively studied. S and Te show similar features, while Se is unique. S and Te have optical absorption edges at wavelengths of ~400 nm with transmission dips at ~450 nm, while Se has the edge at ~550 nm. The three materials provide photoluminescence at visible wavelengths, with intensities of S and Te being stronger than that of Se by two orders. These optical properties imply that S and Te in the zeolite form small atomic units such as S3 and Te2, while Se condenses into single-chain structures.
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