Electrical and optical properties

Oxides. Although not widespread commercially, glass-ceramics consisting of various oxide crystals in a matrix of siUceous residual glass offer properties not available with mote common siUcate crystals. In particular, glass-ceramics based on spinels and perovskites can be quite refractory and can yield useful optical and electrical properties. 

Table 3. Optical and Electrical Properties of DADC Homopolymer, ...

Behavior. Diffusion, Brownian motion, electrophoresis, osmosis, rheology, mechanics, and optical and electrical properties are among the general physical properties and phenomena that are primarily important in coUoidal systems (21,24—27). Of course, chemical reactivity and adsorption often play important, if not dominant, roles. Any physical and chemical feature may ultimately govern a specific industrial process and determine final product characteristics. 

Sulfur reacts with nitrogen to form polymeric sulfur nitrides (SNx) or polythiazyls. These polymers were found to have the optical and electrical properties of metals. ... 

A polymorph is a solid crystalline phase of a compound resulting from the possibility of at least two different crystal lattice arrangements of that compound in the solid state [42], Polymorphs of a compound are, however, identical in the liquid and vapor states. They usually melt at different temperatures but give melts of identical composition. Two polymorphs of a compound may be as different in structure and properties as crystals of two different compounds [43,44], Apparent solubility, melting point, density, hardness, crystal shape, optical and electrical properties, vapor pressure, etc. may all vary with the polymorphic form. The polymorphs that are produced depend upon factors such as storage temperature, recrystallization solvent, and rate of cooling. Table 2 suggests the importance of polymorphism in the field of pharmaceutics [45],... 

Zirconia nanopowders have attracted much attention recently due to their specific optical and electrical properties [38] and as catalysts [39]. Liang et al. [40] have synthesized pure Zr02 nanopowders via sonochemical method. In this study, the use of ultrasound has dramatically reduced the temperature of reaction and made the reaction conditions very easy to maintain. 

Doping is important for semiconductors in order to tune their optical and electrical properties for the potential applications in biotechnology and solar cells [65]. Ag-doped hexagonal CdS nanoparticles were successfully obtained by an ultrasound-assisted microwave synthesis method. Here, the doping of Ag in to CdS nanoparticles induced the evolution of crystal structure from cubic to hexagonal. Further support from photocatalytic experiment also clearly indicates the doping of Ag clusters into the CdS matrix. 

A large number of compounds of pharmaceutical interest are capable of being crystallized in either more than one crystal lattice structure (polymorphs), with solvent molecules included in the crystal lattice (solvates), or in crystal lattices that combine the two characteristics (polymorphic solvates) [122,123]. A wide variety of structural explanations can account for the range of observed phenomena, as has been discussed in detail [124,125]. The pharmaceutical implications of polymorphism and solvate formation have been recognized for some time, with solubility, melting point, density, hardness, crystal shape, optical and electrical properties, vapor pressure, and virtually all the thermodynamic properties being known to vary with the differences in physical form [126]. 

A turning point in the study of amorphous semiconductors was reached with the discovery that the addition of hydrogen to amorphous silicon could dramatically improve the material s optical and electrical properties. Unlike pure amorphous silicon, which is not photoconductive and cannot be readily doped, hydrogenated amorphous silicon (a-Si H) displays a photoconductive gain of over six orders of magnitude and its dark conductivity can be changed by over ten orders of magnitude by n-type or p-type... 

G.E. Jellison, Jr., Optical and Electrical Properties of Pulsed Laser-Annealed Silicon R.F. Wood and G.E. Jellison, Jr., Melting Model of Pulsed Laser Processing R.F. Wood and F.W. Young, Jr., Nonequilibrium Solidification Following Pulsed Laser Melting... 

Kale, R. B. Lokhande, C. D. 2005. Influence of air annealing on the structural, morphological, optical and electrical properties of chemically deposited ZnSe thin films. Appl. Surf. Sci. 252 929-938. 

Mane, R. S. Lokhande, C. D. 2003. Studies on structural, optical and electrical properties of indium sulfide thin films. Mater. Chem. Phys. 78 15-17. 

In analogy to its complexes with nitrosyl cation (as described above), benzene can form donor-acceptor adducts with a variety of metallic and non-metallic Lewis acids. These lead to materials with novel optical and electrical properties that can be tuned through substituents on the aromatic ring. 

S. Beaupre and M. Leclerc, Optical and electrical properties of TT-conjugated polymers based on electron-rich 3,6-dimethoxyfluorene unit, Macromolecules, 36 8986-8991, 2003. 

W.G. Haines and H.R. Bube, Effects of heat treatment on the optical and electrical properties of indium-tin oxide films, J. Appl. Phys., 49 304—307, 1978. 

Structural effects on properties were also studied in detail by a group from Tohoku University, who prepared poly(methylphenylsilylene) (PMPS Mv = 3,120, Mw/Mn = 1.76) and poly(phenylsilyne) (131 poly(penfafluorophenylrilyne)(PPS) 4/w = 1,090, Mw/M = 1.30) by Wurtz-type coupling using sodium and 18-crown-6 in hot toluene and compared their optical and electrical properties.359,360... 

---