Platinum absorption spectra

Figure 5. X-ray absorption spectrum of a silica supported platinum-iridium catalyst at 100 K in the region of the L absorption edges of platinum and iridium. Reproduced with permission from Ref. 13. Copyright 1982, American Institute of Physics.

For a comparison of experimental Mossbauer isomer shifts, the values have to be referenced to a common standard. According to (4.23), the results of a measurement depend on the type of source material, for example, Co diffused into rhodium, palladium, platinum, or other metals. For Fe Mossbauer spectroscopy, the spectrometer is usually calibrated by using the known absorption spectrum of metallic iron (a-phase). Therefore, Fe isomer shifts are commonly reported relative to the centroid of the magnetically split spectrum of a-iron (Sect. 3.1.3). Conversion factors for sodium nitroprusside dihydrate, Na2[Fe(CN)5N0]-2H20, or sodium ferrocyanide, Na4[Fe(CN)]6, which have also been used as reference materials, are found in Table 3.1. Reference materials for other isotopes are given in Table 1.3 of [18] in Chap. 1. 

Henglein A, Ershov BG, Malow M (1995) Absorption spectrum and some chemical reactions of colloidal platinum in aqueous solution. J Phys Chem 99 14129-14136... 

Figure 4a. Absorption spectrum of CO2 radical adsorbed on platinum in acetonitrile containing 0.4M LiClO. (Reproduced with permission from Ref. 11. Copyright 1987 North Holland.)...

The PtCl42 ion, with the 2- - oxidation state for platinum, possesses a 5d8 configuration. It has a square-planar coordination, which is commonly observed with the low spin complexes of this configuration. Its absorption spectrum in aqueous solution is also shown in Figure 1. With the platinum in a low oxidation state, the charge transfer bands have been shifted to beyond 40,000 cm"1. 

Figure 1. Reduced-minus-oxidized difference absorption spectrum of Ps. aeruginosa azurin. Sample and reference cell contained 6.8 X 10 5 M solutions of reduced and oxidized protein, respectively. Hydrogen, with platinum black as catalyst, was used as reductant (1). Medium ...

Chloro(2,2 6, 2"-terpyridine)platinum(II) chloride is a red-orange crystalline compound. It is very soluble in water, but only slightly soluble in polar organic solvents, such as acetone. The electronic absorption spectrum is dependent on the chloride ion concentration and may be used to determine purity. Spectral bands follow Beer s law up to a concentration of 15 juM. At neutral pH in 0.1 Af NaCl the compound has the following absorption maxima and molar extinction coefficients (given in parentheses) 343 (11,300), 327 (12,600), 278 (25,100), and 248 (28,800) nm. 

Reactions of neutral platinum complexes with nucleic acid components in vitro. Changes in the ultraviolet absorption spectrum of salmon sperm DNA after reaction with either cis or... 

Fig. 27. Potential dependence of the IR reflection absorption spectrum of the linearly adsorbed CO on a platinum electrode in 5M CH3OH + 1M HC104.

Fig. 30. Change of the IR reflection absorption spectrum of the linearly adsorbed CO on a platinum electrode with potential (a) in the hydrogen region between 0.5 and 0.35 V (NHE) and (b) across the hydrogen region into the double layer region. Curve 1, 0.15 V (NHE) curve 2, 0.30 V (NHE) curve 3, 0.35 V (NHE) curve 4, 0.40 V (NHE) curve 5, 0.425 V (NHE) curve 6, 0.450V (NHE) curve 7, 0.475V (NHE) curve 8, 0.50 V (NHE).

Magnanini studied the absorption spectrum and A. Speransky found that the electrical conductivity of aq. soln. shows that only a small proportion of the salt is ionized. The soln. of the violet modification conducts electricity three times better than that of the green. G. Gore electrolyzed a cone. soln. of chromic fluoride acidified with hydrofluoric and hydrochloric acids, and found that the liquid became hot no gas was liberated at the cathode, but chlorine and ozone were liberated at the platinum anode which was not corroded. C. Poulenc showed that the salt is reduced by hydrogen at dull redness. The heat of formation is 230-95 Cals, per mol—vide infra, the dichloride. Steam transforms chromic fluoride into chromic oxide. Chromic fluoride is insoluble in water, and alcohol hydrogen chloride transforms it into chromic chloride hot hydrochloric, sulphuric, and nitric acids attack chromic fluoride only a little hydrogen sulphide converts it into black sulphide and molten alkali nitrate or carbonate converts it into chromate. A. Costachescu prepared complex pyridine salts. 

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