화학공학소재연구정보센터
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, Vol.246, 119-125, 1994
Photochromism Based on the Reversible-Reaction of Singlet Oxygen with Aromatic-Compounds
The photolysis of the endoperoxides anthrabisbenzothiopyran (ABTPO) and of benzobisthioxanthene (BTXPO) has been studied in the wavelength range from 333 to 248 nm. At lambda = 248 nm maximum quantum yields ac of 0.09 (ABTPO) and 0.10 (BTXPO) are found for the photocycloreversion reaction. Besides photocycloyeversion a rearrangement reaction takes place with quantum yields Q(R)(248) of 0.013 for ABTPO and 0.018 for BTXPO. Furthermore the selfsensitized photooxygenation of ABT and BTX has been investigated in the concentration range from 10(-5) to 10(-4) M. The mean values of the quantum yield ($) over bar Q(P) were found to be 0.02 (ABT) and 0.05 (BTX). The results indicate that ABT and BTX and their corresponding endoperoxides are components of highly reversible photochromic systems.