Niobium Optical properties

Barium sodium niobium oxide [12323-03-4] Ba2NaNb 02, finds appHcation for its dielectric, pie2oelectric, nonlinear crystal and electro-optic properties (35,36). It has been used in conjunction with lasers for second harmonic generation and frequency doubling. The crystalline material can be grown at high temperature, mp ca 1450°C (37). 

Tantalum and niobium are added, in the form of carbides, to cemented carbide compositions used in the production of cutting tools. Pure oxides are widely used in the optical industiy as additives and deposits, and in organic synthesis processes as catalysts and promoters [12, 13]. Binary and more complex oxide compounds based on tantalum and niobium form a huge family of ferroelectric materials that have high Curie temperatures, high dielectric permittivity, and piezoelectric, pyroelectric and non-linear optical properties [14-17]. Compounds of this class are used in the production of energy transformers, quantum electronics, piezoelectrics, acoustics, and so on. Two of... 

The remarkable optical properties displayed by hydrosols of vana- dium pentoxide (see p. 58) have not hitherto been observed with niobium pentoxide or tantalum pentoxide. 

Preparation of Metallic Niobium—Physical Properties of the Metal, Optical Properties, Arc Spectrum—Chemical Properties—Electromotive Behaviour —Atomio Weight—Alloys. 

Ozer N., Baretto T., Bu5mldimanli T., Lampert C.M. Characterization of sol-gel deposited niobium pentoxide films for electrochromic devices. Sol. Energy Mater. Sol. Cells 1995 36 433-413 Ozer N., Lampert C.M. Structural and optical properties of sol-gel deposited proton conducting Ta20s films. J. Sol-Gel Sd. TechnoL 1997 8 703-709 Ozer N., Lampert C.M. Electrochemical characterization of sol-gel deposited coatings. Sol. Energy Mater. Sol. Cells 1998 54 147-156... 

Our life would never be as advanced and comfortable as it is if not for the applications of tantalum and niobium. These materials unique properties ensure their increasing usage in electronic, optic, mechanical, aerospace, nuclear and other modem applications. 

Since niobates and tantalates belong to the octahedral ferroelectric family, fluorine-oxygen substitution has a particular importance in managing ferroelectric properties. Thus, the variation in the Curie temperature of such compounds with the fluorine-oxygen substitution rate depends strongly on the crystalline network, the ferroelectric type and the mutual orientation of the spontaneous polarization vector, metal displacement direction and covalent bond orientation [47]. Hence, complex tantalum and niobium fluoride compounds seem to have potential also as new materials for modem electronic and optical applications. 

Thus, the behavior in both the titanium and niobium systems is consistent with the hypothesis that the A-site cation is primarily responsible for variation in flat-band potential while the structure is primarily responsible for variation in optical band gap. Of course, it has been noted elsewhere that other properties such as the magnitude of the quantum efficiency also depend upon structure (10). 

Lithium niobate [niobium + -ate[ (1966) n. LiNb03. A crystaUine material whose physical properties change in response to pressure or the presence of an electric field and which is used in fiber optics and as a synthetic gemstone. 

CY Allison, FA Modine, RH French. Optical and electrical properties of niobium carbide. Phys... 

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