Iron optical properties

An example of this process of data analysis is provided by the work of Yubero et al. (2000), who studied the structure of iron oxide thin films prepared at room temperature by ion beam induced chemical vapour deposition. Such films find important applications because of their optical, magnetic, or magneto-optical properties. They were produced by bombardment of a substrate with Oj or Oj + Ar+ mixtures, and Figure 4.15 shows RBS spectra of two iron oxide thin films prepared on a Si substrate by each of these bombardment methods. 

Opaque minerals like iron oxides are frequently examined in the reflectance mode - and usually give diffuse reflectance spectra. Reflectance spectra provide information about the scattering and absorption coefficients of the samples and hence their optical properties. The parameters of reflectance spectra may be described in four different ways (1) by the tristimulus values of the CIE system (see 7.3.3) (2) by the Kubelka-Munk theory and (3) by using the derivative of the reflectance or remission function (Kosmas et al., 1984 Malengreau et ak, 1994 1996 Scheinost et al. 1998) and, (4) more precisely, by band fitting (Scheinost et al. 1999). 

Rates of sorption and desorption of phosphate. Eur. J. Soil Sd. 48 101-114 Strens, R.G.S. Wood, B.J. (1979) Diffuse reflectance spectra and optical properties of some iron and titanium oxides and oxyhydr-oxides. Min. Mag. 43 347—354 Stumm, W. Eurrer, G. (1987) The dissolution of oxides and aluminum silicates Examples of surface-coordination-controlled kinetics. 

Optical properties of liquids are similar in many ways to those of solids. Electrically, there are metallic liquids such as mercury and molten iron, but the majority of common liquids are nonmetallic. As an illustration of a liquid we have chosen H20, a ubiquitous substance on our planet water dominates not only atmospheric processes but the chemistry of life. 

The IR spectra (402) and thermal decomposition (396) of the FeO 3B203 xH20 borates have been measured. The anhydrous iron borates FesBOs and FeB03 exhibit interesting magnetic and magneto-optical properties. In the last 10 years, well over 50 papers have been written on these borates, a few of which have been summarized by Bowden and Thompson (60). 

These results pave the way to functional nanoparticles where the size, shape, and iron oxide concentration can be controlled leading to tunable magnetic and optical properties of nanostructures on surfaces and interesting research in catalysis, molecular labeling, and detection, as well as controlled dmg delivery using external magnetic fields. 

Addition of potassium hydroxide to a solution of the alum, and subsequent evaporation yields a crop of crystals yellowish brown in colour and possessing peculiar optical properties like tourmaline. Their composition is given as 5K2S04.2Fe2(S04)2.(0H)2.16H20. The crystals decompose to iron alum and a basic salt. 

Schlegel, A., and P. Wachter (1976). Optical properties, phonons and electronic structure of iron pyrite (FeSj). J. Phys. C9, 3363-69. 

Experiments have established that there are four polymorphs in solid iron (a-, y-, S-, and s-phases). Saxena et al (1993) proposed a fifth iron phase (/3-phase) based on changes in thermal emission while laser heating the sample in a diamond-anvil cell. Boehler (1993) also observed similar changes in optical properties of iron in the same P-T range. Subsequent in situ X-ray diffraction measurements in the laser-heated diamond-anvil cell supported the occurrence of this new iron phase, although the structure of this phase is still under debate (Saxena et al, 1996 Yoo et al, 1996 Andrault et al, 1997, 2000 Saxena and Dubrovinsky, 2000). However, this phase was not observed in... 

With few exceptions, a useful nonlinear optical material will be in the solid phase for example, a single crystal or a poled polymer embedded in a film. Ironically, the quantum chemical calculations of nonlinear optical properties have for the most part been concerned with a single microscopic species. Much has been learned in this way about appropriate molecular construction, but the ultimate goal must be to investigate the nonlinear optical (NLO) properties in the solid phase. 

Powell, C.E., Cifuentes, M.P., McDonagh, A.M., Hurst, S.K., Lucas, N.T., Delfs, C.D., Stranger, R., Humphrey, M.G., Houbrechts, S., Asselberghs, I., Persoons, A., Hockless, D.C.R. OrganometalUc complexes for nonUnear optics. Part 27. Syntheses and optical properties of some iron, ruthenium and osmium alkynyl complexes. Inorg. Chim. Acta 352, 9-18 (2003)... 

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