Fast Photoswitching Azo Dyes

Abstract

Summary: Fast photoswitching azobenzene molecules were incorporated into isoflavone moieties. These molecules exhibit a liquid crystalline nematic state at certain temperature intervals. UV/Vis spectrophotometry investigations on solutions reveal that E/Z conversion takes place around 1 s, whereas thermal back relaxation, namely Z/E, takes around 6 min. This is the first example of fast photoswitching isoflavones in solution. This study has potential to create optical data storage devices when transferred to solid surfaces.

Photochemical anti–syn isomerization around the –N–N bond in heterocyclic imines

“…3,4 Systems possessing a double bond between two atoms with bulky substituents tend to undergo an isomerisation process, 5 but then relax back to the more stable isomer by thermal relaxation or when exposed to a particular wavelength of light. 6,7 The re-isomerisation process can sometimes proceed very rapidly, especially in the case of highly-conjugated systems with small substituents and an aliphatic backbone. 8 On the other hand, some systems relax signicantly more slowly and relax to the lower-energy isomer only aer days or months.…”

Synthesis and Light Induced Characteristics of Siloxane Substituted Azobenzene: An Application for Optical Storage Device

“…Mainly, azobenzene compounds have great importance in liquid crystal research [4,12,13] and the special characteristics of azobenzene can be employed in many areas of research such as photoalignment [14,15], holographic media [16,17], and optical storage [18,19]. Moreover, some of the azo dyes are not liquid crystals in nature.…”