Langmuir-Blodgett films electrical properties

Nakamura T, Yunome G, Azumi R, Tanaka M, Tachibana H, Matsumoto M, Horiuchi S, Yamochi H, Saito G (1994) Structure and electrical properties of the metallic Langmuir-Blodgett film without secondary treatments. J Phys Chem 98 1882-1887... 

Photochemical switching of the electrical properties of conductive Langmuir-Blodgett films results from photoinduced conformational changes produced by an azobenzene unit [8.253]. 

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. 

P.S. Vincett, G.G. Roberts, Electrical and Photo-Electrical Transport Properties of Langmuir-Blodgett Films and a Discussion of Possible Device Applications , Thin Solid Films, 68, 135 (1980)... 

Brynda E, Koropecky I, Kalvoda Land Nespurek S 1991 Electrical and photoelectrical properties of copper tetra[4-tert-butylphthalocyanine] Langmuir-Blodgett-films Thin Solid Films 199 375-84... 

It follows from the definitions above that for measuring the electrooptic coefficients, one should measure the index variation due to the application of an electric field. Evanescent waves coupled by the ATR method to surface plasmons or to waveguide modes have been demonstrated as useful tools for measuring electrooptical properties of NLO Langmuir-Blodgett films and NLO polymers [81-85],... 

Jung, G.Y., et al. 2000. The effect of insulating spacer layers on the electrical properties of polymeric Langmuir-Blodgett film light emitting devices. / Phys D Appl Phys 33 1029-1035. 

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

The above devices inspired scientists to develop solid-state MSTJ devices made from a [2]pseudorotaxane and [2]rotaxane (Figure 76) in which hydrophobic and hydrophilic regions were directly incorporated into the molecular structure to allow self-organization. ° The electrical properties were found to be highly dependent on the supramolecular structure, the presence of bistability within the (super)molecule, and the organization of the Langmuir-Blodgett film. The devices exhibited a... 

In view of the potential technological importance of noncentrosymmetric organic crystals, several approaches have been evolved to artificially achieve noncentrosym-metry, which include electric field poling of polymers, self-assembly of molecular layers, Langmuir-Blodgett assembly of films and host-guest interaction in noncentrosymmetric hosts (Marder et al, 1994). Prediction and/or control of the three-dimensional structure of crystals, given only the information of molecular properties, however, remains difficult at present. 

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