Photochemically triggered systems

Photochemically Triggered Physical Amplification of Photoresponsiveness in Molecular Aggregate Systems... 

Tazuke, S. Kurihara, S. Ikeda, T. Amplified image recording in liquid crystal media by means of photochemically triggered phase transition. Chem. Lett. 1987, 76(5), 911-914. Seki, T. Dynamic photoresponsive functions in organized layer systems comprised of azobenzene-containing polymers. Polymer J. 2004, 36, 435 54. 

A compound with a highly temperatine-dependent property, such as solubility, is said to be thermomorphic. There are a variety of other catalyst systems that can be recovered on the basis of temperature-dependent solubilities, usually involving polymers [13-18]. Attention has also been given to nonthermal solubility switches . These include photochemically and chemically triggered precipitons [19-25], and the use of CO2 pressure to regulate solubilities [26-28]. The latter protocol is particularly suited to liuorous compounds. 

X 109 and 8. 9 x 109 s 1 for Ndm and Ybm, respectively. Both the above-described in-termolecular mechanism, as well as an intramolecular pathway in the ternary complex with aad which forms in solution, are responsible for the observation of NIR luminescence in these systems. Addition of water to the toluene solutions quenches the NIR luminescence, while it enhances the visible CL emission of the corresponding solution of Eum and Tbm (Voloshin et al., 2000c). Neodymium and ytterbium tris(benzoyltrifluoroacetonates) display the same CL as tta complexes, although for Ybm its intensity is about 2.5 times lower than for the tta chelate. On the other hand, almost no CL is detected for acetylacetonate complexes (Voloshin et al., 2000a). Thermal or photochemical decomposition of aad also triggers CL from [Pr(dpm)3] and Pr(fod)3], both in the visible (from the 3Pi, 3Po, and 1D2 levels) and in the NIR at 850 nm ( Do -> 3F2 transition) and 1100 nm ( D2 3F4 transition). The excited... 

A cumulative success of artificial ion-channel functions by simple molecules may disclose a wide gate for the design of ion channels and possible applications to ionics devices. Incorporation of these channels into bilayer lipid membrane systems may trigger the developments towards ionics devices. The conventional BLM system, however, is not very stable, one major drawback for the practical applications, and some stabilization methods, such as impregnating the material in micro-porous polycarbonate or polyester filters, are required.127 132-137 On the other hand, the conventional LB technique prohibits rapid photochemical reactions of incorporated chromophores and many efforts to overcome the problems have been made.138-141... 

In previous chapters, detailed theoretical principles of CT processes in general and photoinduced CT processes in particular have been provided. The next step is the practical application of these principles to systems which will be discussed within the scope of this thesis, namely organic -conjugated donor-acceptor supramo-lecular assemblies. Furthermore, we will draw our attention to CT processes, which are triggered by photochemical stimuli. They provide the theoretical background, which is required to understand the charge-transport properties of wire-type molecular bridges. 

The convenient triggering of selective reactions by light and the regulatory effects of light intensity variations are crucial benefits of the photochemical approach toward biomimetic model compounds. These two important aspects of biological systems, which are otherwise hardly achieved in synthetic molecular devices, will be briefly discussed in the following sections. 

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