Azobenzene-based photochromic

Nakano H, Takahashi T, Kadota T, Shirota Y. 2002. Formation of the surface relief grating using a novel azobenzene based photochromic amorphous molecular material. Adv Mater 14 1157 1160. 

Tanino T, Yoshikawa S, Ujike T, Nagahama D, Moriwaki K, Takahashi T, Kotani Y, Nakano H, Shirota Y. 2007. Creation of azobenzene based photochromic amorphous molecular materials synthesis, glass forming properties, and photochromic response. J Mater Chem 17 4953 4963. 

Nakano, H. Takahashi, T. Kadota, T. Shirota, Y. (2002). Formation of Surface Relief Grating Using a Novel Azobenzene-based Photochromic Amorphous Molecular Material. Ado. Mater., 2002,14,1157-1160. 

This chapter discusses photochromic azobenzene polymers and photochromic molecules capable of undergoing photodimerization as materials for potential use in optical data storage applications. A brief introduction to photochromism, including recent examples of some photochromic systems, other than azobenzenes, based on variety of applications is presented at the outset. Thereafter, we shall focus on azobenzene photoaddressable polymers (PAPs) and [4 + 4]-photocycloaddition as materials for ultrahigh capacity optical data storage. 

Hafiz, HR. and Nakanishi, F. (2003) Photoresponsive liquid crystal display driven by new photochromic azobenzene-based Langmuir-Blodgett films. Nanotechnology, 14, 649-654. 

Photochromism Based on Geometric Isomerism. The simplest examples of a photochromic reaction involving reversible cis-trans isomerization is the photoisomerization of azobenzene [103-33-3] C22H2QN2 (16). 

The peak shift due to aggregation is observed not only in LBK films containing azobenzene chromophores, but also for other chromophores with extended Ji-systems, such as viologen polymers. For monolayers of the poly(p-phenylene sulfonate) 9/ dioctadecyldimethylammonium bromide (DODA) complex, the peak shift due to aggregation results in a piezo-chromic effect—that is, upon compression of the monolayer, a significant shift of the poly(p-phenylene sulfate) A band is observed (see Figure 6.9). This photochromic effect has been shown to be based on the improved 7t-Jt interaction upon compression of the monolayer. ... 

The ability of azobenzene derivatives to isomerize in the CD cavity with good yields stimulated the preparation of Langmuir-Blodgett films, based on amphiphilic modified CDs, including aromatic azo compounds, with excellent photochromic properties [306]. 

Matejka et al. synthesized several types of photochromic polymers based on a copolymer of maleic anhydride and styrene with azobenzene moieties both in the side chains and cross-links of the polymer network (Matejka et al., 1981 Matejka and Dusek, 1981 Matejka et al., 1979). The photomechanical effect was enhanced by an increase in the content of photochromic groups, and the photoinduced contraction of the sample amounted to 1% for a polymer with 5.4mol% azobenzene moieties. 

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