Tailoring optical properties

Lately, the CP-MD approach has been combined with a mixed QM/MM scheme [10-12] which enables the treatment of chemical reactions in biological systems comprising tens of thousands of atoms [11, 26]. Furthermore, CP-MD and mixed QM/MM CP-MD simulations have also been extended to the treatment of excited states within a restricted open-shell Kohn-Sham approach [16, 17, 27] or within a linear response formulation of TDDFT [16, 18], enabling the study of biological photoreceptors [28] and the in situ design of optimal fluorescence probes with tailored optical properties [32]. Among the latest extensions of this method are also the calculation of NMR chemical shifts [14]. 

V. 1. Boev et al., Flexible ureasil hybrids with tailored optical properties through doping with metal nanoparticles, Langmuir, 20(23), 10268-10272 (2004). 

Chen,)., Wang, D Xi, Au, L, Siekkinen, A., Warson, A., li, Z.-Y., Zhang, H., Xia, Y. and li, X. (2007) Immuno gold nanocages with tailored optical properties for targeted photothermal destruction of cancer cells. Nano Letters, 7,1318 22. 

Since multiple electrical and optical functionality must be combined in the fabrication of an OLED, many workers have turned to the techniques of molecular self-assembly in order to optimize the microstructure of the materials used. In turn, such approaches necessitate the incorporation of additional chemical functionality into the molecules. For example, the successive dipping of a substrate into solutions of polyanion and polycation leads to the deposition of poly-ionic bilayers [59, 60]. Since the precursor form of PPV is cationic, this is a very appealing way to tailor its properties. Anionic polymers that have been studied include sulfonatcd polystyrene [59] and sulfonatcd polyanilinc 159, 60]. Thermal conversion of the precursor PPV then results in an electroluminescent blended polymer film. 

The pace of development has increased with the commercialization of more engineering plastics and high performance plastics that were developed for load-bearing applications, functional products, and products with tailored property distributions. Polycarbonate compact discs, for example, are molded into a very simple shape, but upon characterization reveal a distribution of highly complex optical properties requiring extremely tight dimension and tolerance controls (3,223). 

The m-V and II-VI semiconductor compounds have excellent optical properties and are the most important group of optoelectronic materials, which are all produced by CVD for many optoelectronic applications. The properties of these materials and their CVD reactions are reviewed in Ch. 12, Secs. 3.0 and 4.0 and Ch. 13, Sec. 6.0. It is possible to tailor the bandgap, by the proper combination of these materials, to suit any given application (See Fig. 13.2 of Ch. 13). 

In 1996, Wegner et al. published the synthesis of poly(oligophenylenevinyle-ne)s (96), consisting of biphenylene-, terphenylene- and quinquephenylene moieties as aromatic building blocks, via Suzuki-type aryl-aryl cross coupling of AA/BB-type monomers [121]. By judicious choice of the arylene moieties, the optical properties of the resulting polymers can be tailored within a wide range. 

Another example of recent work is the demonstration of non linear optical properties of Cu nanoparticles in an ITO matrix.62 This is an example of a structure that can be obtained fully by solution processing. Coupled with this is the observation of enhanced surface plasmons in some nanoparticles, which potentially produces tailorable, non linear optical properties.63 This effect can... 

In the past three decades, ti-conjugated (semi)conducting polymers have attracted significant interest, since these materials may combine the ease of processibility and outstanding mechanical properties of polymers with the exceptional, readily tailored electronic and optical properties of functional organic molecules [1,2]. Especially the potential use of these synthetic metals ... 

We have overviewed some strategies for the surface-mediated fabrication of metal and alloy nanoscale wires and particles in mesoporous space, and their structural characterization and catalytic performances. Extension of the present approaches for metal/alloy nanowires may lead to the realization of the prospechve tailored design of super active, selective and stable catalysts applicable in industrial processes. The organometallic clusters and nanowires offer exciting and prospechve opportunities for the creahon of new catalysts for industry. Various metal/ alloy nanowires and nanoparhcles in the anisotropic arrangement in porous supports would help in understanding the unexpected electronic and optic properties due to the quantum effect, which are relevant to the rational design of advanced electronic and optic devices. 

The properties of the final polymer (melting point, solubility, optical properties, etc) depend on the nature of the side chain incorporated into the structure, so that judicious choice of substituent can lead to material tailorability. 

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