Langmuir-Blodgett films optical properties

Nonlinear Optical Properties of Langmuir-Blodgett Films Containing C60 and Derivatives... 

The material system is a Langmuir-Blodgett film of the S enantiomer of a chiral polymer deposited on a glass substrate. The polymer is a poly(isocyanide)30 functionalized with a nonlinear optical chromophore (see Figure 9.14). In this particular system the optical nonlinearity and chirality are present on two different levels of the molecular structure. The chirality of the polymer is located in the helical backbone whereas the nonlinearity is present in the attached chromophores. Hence, this opens the possibility to optimize both properties independently. 

Multilayer Langmuir-Blodgett films doped with a cyanine dye have been deposited on the surface of a quartz multimode optical fiber and the fluorescence properties investigated. 49 The fluorescence intensity of the films was found to be a periodic function of the number of layers due to the waveguide properties of the films. 

Because of their electrical, optical, and redox properties as well as the thermal and chemical stability, the Pcs also have been tried in the detection of volatile organic compounds and poisonous gases, which is very important for environment and human health. In the past decades, the possible applications of Pc thin film as sensor for atmospheric gaseous pollutants have been extensively studied [73, 74], Langmuir-Blodgett films of some multinuclear and multidouble-decker lutetium Pcs have also been used for those measurements [75,76], More details about conductivity and sensing properties of Pcs can be found elsewhere [77,78]. 

Chirality is a very general symmetry concept, and its consequences are not limited to the optical properties of systems. An electrical conductor for instance may be chiral because of several reasons. The material may crystallize in a chiral space group, like tellurium or /9-manganese [30], or be composed of chiral subunits like chiral conducting polymers [31] and Langmuir-Blodgett films [32] or vapors [33] of chiral molecules. Even if the material itself is nonchiral, it may still be formed into a chiral shape, like a helix. In all these cases, the conductor can exist in two enantiomeric forms. 

Nagamura, T., Sakaguchi. H., Matsuo, T. Photochemical modulahon of second order nonhnear optical properties of alternate Langmuir-Blodgett films containing ruthenium) ll)-bipyridine complexes. Thin Solid Films 210-211, 160-162 (1992)... 

J. D. Swalen, Optical properties of Langmuir-Blodgett films, J. Mol. Electron. 2 155... 

Sheng-Gao, L., L. Yun-Qi, Yu Xu, Z. Dao-Ben, Y. An-Chi, and Z. Xing-Sheng (1998). Synthesis, Langmuir-Blodgett film, and second-order nonlinear optical property of a novel asymmetrically substituted metal-liee phthalocyanine. Langmuir 14, 690. 

Munn et have attempted to relate the macroscopic refractive indices and susceptibility tensor for the iodoform and sulfur (Sg) crystals and the crystalline complex CHal.SSg to the molecular polarizabilities and hyperpolarizabilities. The attempt is only partially successful and illustrates the difficulties that will be encountered in projects such as that described in ref. 246. Penhuis and Muim have performed calculations of the linear and non-Unear optical properties of layers of Langmuir-Blodgett films and find that the internal field varies little after the first layer. They have investigated Langmuir-Blodgett... 

Pure and mixed chlorophyll a Langmuir and Langmuir-Blodgett films. Structure, electrical and optical properties... 

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