1092363-98-8Relevant articles and documents
Photochemistry of 3,6-bis(styryl)pyridazines in solution and in neat liquid crystalline phase-optical switching and imaging techniques
Meier, Herbert,Lifka, Thorsten,Seus, Peter,Oehlhof, Annette,Hillmann, Sabine
, p. 10754 - 10760 (2008/12/23)
3,6-Bis(styryl)pyridazines 1a-f with 2-6 alkoxy groups show on irradiation in solution a stereoisomerization which leads to a photostationary state of (E,E)- and (E,Z)-isomer. Sensitizing and quenching experiments reveal that the (E,E)→(E,Z) route is a pure triplet process, whereas the (E,Z)→(E,E) route can have a minor singlet by-reaction. Hexyloxy or dodecyloxy chains on the terminal benzene rings convey the (E,E)-isomers of compounds 1a,b,d-f thermotropic liquid crystalline properties. In particular SA, SC, and SF/I phases were studied with regard to their photochemical behavior. Depending on the system, photodegradation of the smectic phase to the isotropic melt (S→I) or photoinduction of the smectic phase (I→S) can be achieved by alteration of the (E,E)/(E,Z) ratio. These processes represent the basis for imaging techniques (writing and erasing of information).
