Materials, optical properties

Andrzejewski D., Podbielska H., Mutual influences of sol-gel matrices and dopants on the materials optical properties, Opt. Appl. 2001 31 223-229. 

Materials—Optical properties—Congresses. 2. Stereochemistry— Congresses. 3. Nonlinear optics—Congresses. 

I. Honma and H.S. Zhou, Self-assembling Functional Molecules in Mesoporous Silicate Materials Optical Properties and Mesophase of Dye-doped M41S. Adv. Mater., 1998, 10, 1532-1536. 

Superconductors. 2. Organic conductors. 3. Magnetic materials—Optical properties. 

It is important to consider a materials optical properties throughout the entire solar spectrum (approximately 300 to 2500 nm) rather than just the visible spectrum or just the IR spectrum since about half of the solar energy is composed of wavelengths less than 780 nm and half the solar energy lies above 780 nm... 

Honma L, Zhou H.S. Self-assemhling functional molecules in mesoporous silicate materials Optical properties and mesophase of dye-doped M41S. Adv. Mater. 1998 10 1532-1537 Honma L, Zhou H.S., Kundu D., Endo A. Structural control of surfactant-templated hexagonal, cubic and lamellar mesoporous silicate thin films prepared by spin-casting. Adv. Mater. 2000 12 1529-1533... 

In a heterodyne-detected transient-grating (HD-TG) experiment [5,8-11], two infrared laser pulses, typically obtained dividing a single pulsed laser beam, interfere within the sample producing an impulsive spatially periodic variation of the material optical properties. The spatial modulation is characterized by a wave vector which is given by the difference of the two pump wave vectors. The relaxation toward equilibrium of the induced modulation is probed by measuring the Bragg scattered intensity of a second continuous wave laser beam. A sketch of the experimental set-up and details on the laser systems can be found in ref 5 and ref. 10, respectively. 

Actual crystal planes tend to be incomplete and imperfect in many ways. Nonequilibrium surface stresses may be relieved by surface imperfections such as overgrowths, incomplete planes, steps, and dislocations (see below) as illustrated in Fig. VII-5 [98, 99]. The distribution of such features depends on the past history of the material, including the presence of adsorbing impurities [100]. Finally, for sufficiently small crystals (1-10 nm in dimension), quantum-mechanical effects may alter various physical (e.g., optical) properties [101]. 

G) ILLUSTRATIVE EXAMPLES OF THE ELECTRONIC AND OPTICAL PROPERTIES OF MODERN MATERIALS... 

The striking size-dependent colours of many nanocrystal samples are one of tlieir most compelling features detailed studies of tlieir optical properties have been among tire most active research areas in nanocrystal science. Evidently, tire optical properties of bulk materials are substantially different from Arose of isolated atoms of tire... 

Chemistry produces many materials, other than drugs, that have to be optimized in their properties and preparation. Chemoinformatics methods will be used more and more for the elucidation and modeling of the relationships between chemical structure, or chemical composition, and many physical and chemical properties, be they nonlinear optical properties, adhesive power, conversion of light into electrical energy, detergent properties, hair-coloring suitabHty, or whatever. 

The study of organic semiconductors and conductors is highly iaterdisciplinary, involving the fields of chemistry, soHd-state physics, engineering, and biology. This article provides a treatment of the theoretical aspects of organic semiconductors as well as an overview of recent advances ia the field and the uses of these materials based on their conductive and optical properties. 

Diamond is supreme among natural gemstones ia H, RI, and DISP. Table 3 shows the steady improvement ia the sequence of diamond imitations, the aim being to produce a colorless, adequately hard material having closely matching optical properties. The iatroduction of synthetic cubic 2irconia ia 1976 brought about a sufficiently close match. 

Several gemstone species occur in various colors, depending on the presence of impurities or irradiation-induced color centers. Examples are the beryl, comndum, and quart2 families. Quart2 has poor optical properties (RI = 1.55, DISP = 0.013), but becomes of gemological interest when it exhibits attractive colors. Any material can have its color modified by the addition of various impurities synthetic mby, sapphires, and spinel are produced commercially in over 100 colors (2). Synthetic cubic 2irconia has been made in essentially all colors of the spectmm (11), but only the colorless diamond imitation is produced commercially in any quantity. 

Certain glass-ceramic materials also exhibit potentially useful electro-optic effects. These include glasses with microcrystaUites of Cd-sulfoselenides, which show a strong nonlinear response to an electric field (9), as well as glass-ceramics based on ferroelectric perovskite crystals such as niobates, titanates, or zkconates (10—12). Such crystals permit electric control of scattering and other optical properties. 

Substituted cyclopentane lubricants have been commercialized using cyclopentadiene as starting material. These specialty aerospace lubricants have low volatihty and desirable optical properties. 

Organic Dye Lasers. Organic dye lasers represent the only weU-developed laser type in which the active medium is a Hquid (39,40). The laser materials are dyestuffs, of which a common example is rhodamine 6G [989-38-8]. The dye is dissolved in very low concentration in a solvent such as methyl alcohol [67-56-17, CH OH. Only small amounts of dye are needed to produce a considerable effect on the optical properties of the solution. 

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