Langmuir-Blodgett assembly

Three-methods have been pursued to organize monolayers from different organic compounds to form molecular monolayer FETs (1) thermal evaporation of approximately monolayer thickness on the dielectric surface of FETs, (2) Langmuir-Blodgett assembly on the water surface and transfer to device surfaces, and (3) self-assembly of functionalized organic compounds on the surface of the gate, or gate dielectric layers of FETs. 

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. 

Figure 11.45 Langmuir-Blodgett assembly of push-pull NLO materials within a fatty acid matrix.

Mahmoud MA, El-Sayed MA (2008) Comparative study of the assemblies and the resulting Plasmon fields of Langmuir-Blodgett assembled monolayers of silver nanocubes and gold nanocages. J Phys Chem C 112(37) 14618-14625... 

Spooner, S. P., and Whitten, D. G. Photoreactions in Monolayer Films and Langmuir Blodgett-Assemblies. In Photochemistry in organized and constrained media, V. Ramanmurthy, Ed. VCH Weinheim (1991), p. 691. 

Sakaguchi, H., Nagamura, T., Penner, T.L., Whitten, D.G. Ultrafast optical modulation of quadratic nonlinearity from an Ru(II)-bipyridine complex in Langmuir-Blodgett assemblies. Thin Sohd Films 244, 947-950 (1994)... 

Yang PD, Rim F (2002) Langmuir-Blodgett assembly of one-dimensional nanostructures. Chemphyschem 3 503-506... 

Langmuir-Blodgett Assembly The Langmuir-Blod-gett (LB) technique has been used to assemble ID nanoscale building scale. Various superstructirres can be obtained as a result of different interactions between the... 

For nonlinear optical molecules which do not possess the desired centrosymmetric crystallization, there are very potent methods to incorporate these chromophores into polymer hosts ( electric field poling ) (Singer et al., 1986,1987 Hubbard et al., 1989 Bjorklund et al., 1991), self-assembly of molecular layers (Li et al., 1990 Katz et al., 1991), and Langmuir-Blodgett assembly of films (Roberts et al 1990 Kajikawa et al., 1992 Marder et al., 1994). 

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