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Absolute integrated intensities of »

In this circumstance, it is more reliable to measure the absolute integrated intensity of the substrate peak and compare this with the integrated intensity from an equivalent crystal of the substrate material on which no layer has been grown. In the angular position for diffraction from the substrate, the layer will not diffract and the substrate peak intensity will be simply reduced by normal photoelectric absorption. For a symmetric reflection, it is easy to see that the integrated intensity 1 of the substrate peak with the layer of thickness t present is related to the integrated intensity of the bare substrate / o by... [Pg.134]

As a means of comparing the absolute integrated intensities of the carbonyl stretching vibrations of a wide range of complexes of varying molecular symmetries and of differing numbers of carbonyl groups, Noack 109) used the specific intensity of each compound. This is defined as the intensity... [Pg.222]

Absolute Integrated Intensities of Pentacarbonyl Metal Derivatives... [Pg.225]

Absolute Integrated Intensities of Arene-Metal Carbonyl Complexes... [Pg.227]

Absolute Integrated Intensities of Polynuclear Metal Carbonyl... [Pg.230]

Tables of K values have been computed by Jones, Ramsey, Herling, and Dobriner J.A.C.S, 74, 2828, 1952) and extended tables have been developed by Sandorfy Spectrochim. Acta 16, 335, 1960). The Sandorfy equation yields absolute integrated intensities of absorption bands if proper slit widths and scan times are used. Tables of K values have been computed by Jones, Ramsey, Herling, and Dobriner J.A.C.S, 74, 2828, 1952) and extended tables have been developed by Sandorfy Spectrochim. Acta 16, 335, 1960). The Sandorfy equation yields absolute integrated intensities of absorption bands if proper slit widths and scan times are used.
An absolute integrated intensity of 1880(290) cmatm" at STP was determined for the Vi band of N2H using the technique of direct laser absorption spectroscopy in fast ion beams. This value [37] supersedes a previous value determined in the same laboratory [38]. Higher values were predicted by high-quality ab initio calculations, CEPA-1 [36] and Ci-SDQ [39]. Integrated Intensities for the V2 [39] and V3 [36, 39] bands of N2H, for the Vi and V3 bands of N2D [36], and for bands from overtones and combinations of the v, and V3 fundamentals of N2H (N2D ) were also predicted in the ab initio calculations [36, 39]. The V3 band was predicted to be about 140 times weaker than the v, band [36], and the V2 band to be about five times weaker than the band [39]. [Pg.24]

The relative degree of crystallinity can also be estimated from the WAXS pattern from the ratio of the integrated intensity of the crystal peak to that of the total amorphous and crystalline scattering (Balta-Calleja and Vonk 1989). For PE, the amorphous scattering below the (110) peak (Fig. 5.7) is relatively insensitive to the degree of crystallinity, so the integrated area of the (110) reflection compared to the broad amorphous halo is directly proportional to XPE. However, the absolute degree of crystallinity cannot be determined in this way (Ryan et al. 1995). [Pg.287]

Further thermodynamic data,10 absolute integrated intensities for the i.r. absorption bands,11 and more Raman data12 have been presented for Cr(CO)6. Core13 and valence region14 photoelectron spectra have been determined for Cr(CO)6 and discussed on the basis of MO data. Examination of the reaction products of Cr atoms with CO at 4.2—10K has established the existence of a Cr(CO)5 species having a D3h, trigonal-bipyramidal stereochemistry. The data obtained using pure... [Pg.87]

Finally some general, practical, but simple, points are well worth attention for studies of transition metal carbonyl derivatives. For optimizing the accuracy of absolute integrated intensities, great care must be taken to minimize errors arising from weighing of the sample, from sample and solvent impurities, and from solvent evaporation. [Pg.208]

Absolute integrated intensities given in all tables are in practical units 109, 125), whereas it must be noted that A as defined in the text [Eq. (8)] is the Ramsay and Jones unit. Conversion factors interrelating some of the various commonly used units of intensity to practical units are to be found in Table VIII. [Pg.224]

In contrast to solution-phase or direct polarization solid-state NMR experiments, CP-MAS is not a truly quantitative technique. As a result of the cross-polarization step, the integral intensities of peaks in CP-MAS spectra do not directly reflect the stoichiometry of nuclei in the molecule. CP-MAS signals originate from protons, and its transfer efficiency varies from carbon to carbon, based on proximity of protons and local mobility of the molecule. In most pharmaceutical applications, only relative concentrations of mixtures of two or more polymorphs need to be determined even in complex dosage forms. The absolute concentration of the drug in formulation is usually known or can be determined by other techniques. [Pg.67]

We can thus make an absolute measurement of the austenite content of the steel by direct comparison of the integrated intensity of an austenite line with the integrated intensity of a martensite line. By comparing several pairs of austenite-martensite lines, we can obtain several independent values of the austenite content. [Pg.412]

The absolute integrated intensities, scattered by an aluminum alloy at 4.4% Zn, allows to deduce the variation of fz with a good accuracy. [Pg.11]

Other shows two bands of equal intensity at 2l0i and 2085 cm . However, their structural difTerences are unknown. Darensbourg obtained a linear relalionship between p(N=N) and the absolute integrated intensity in a series of molecular nitrogen compounds. [Pg.321]

When linearly polarized light is absorbed by a sample, the integrated intensity of the absorption band is proportional to the square of the absolute value of the dot product of the transition dipole vector and the electric field vector of the incident radiation [48, 49] ... [Pg.343]

The position of the v(GeC) band in various alkylgermanes, Ge(CH3)nR4 n, has been studied and correlated with the effective electronegativities of the four substituents [12]. For M(CH3)4 compounds with M = Si, Ge, and Sn, integral intensities of the v(CH) bands were evaluated and their trends within this series discussed [28]. Several publications deal with the IR and Raman spectra of Ge(CH3)nCl4 n compounds (n = 1 to 4) observed and calculated frequencies and force constants were listed [15] v(CH) and v(GeC) intensities were measured and compared with calculated values based on the valence-optical scheme [18, 32] the possibility of applying this scheme in the first approximation to these compounds was considered [37] absolute intensities and degrees of depolarization were calculated (using the same scheme) and compared with experimental values [51]. The nonadditivity of the increase of v(CH) Raman... [Pg.30]

A method for the absolute quantitative determination of crystalline phases in a multiphase mixture is to mix a standard substance into the specimen. Calibration curves are necessary for mixtures of the standard with each of the phases to be determined. The components can then be determined independently of each other. The critical point is to determine accurately the integral intensity of a sufficiently strong reflection that does not have any other reflection superposed on it. With a diffractometer linked to a computer, it is possible to separate overlapping reflections and determine their intensities, although some idealizations are required. [Pg.407]

Fig. 5. XPS spectra of As 3d and In 4d in InAs sample during various stages of its processing in oxygen glow discharge plasma at sample voltage of 350 V (a), experimental values of the relation between integrated intensities of peak components and calculated values of thickness of the formed oxide films (b) ( ) - total relation of As 3d / In 4d peak components intensities ( ) - relation of peak components intensities of As 3d / In 4d connected with the substrate (A) - relation of peak components intensities of As 3d / In4d connected with the oxide film ( ) - calculation of the total thickness of oxide films from the absolute attenuation of As 3d peak from the substrate (o) - calculation of the thickness of oxide films from the ratio of As 3d peak components connected with the oxide film and InAs substrate. Fig. 5. XPS spectra of As 3d and In 4d in InAs sample during various stages of its processing in oxygen glow discharge plasma at sample voltage of 350 V (a), experimental values of the relation between integrated intensities of peak components and calculated values of thickness of the formed oxide films (b) ( ) - total relation of As 3d / In 4d peak components intensities ( ) - relation of peak components intensities of As 3d / In 4d connected with the substrate (A) - relation of peak components intensities of As 3d / In4d connected with the oxide film ( ) - calculation of the total thickness of oxide films from the absolute attenuation of As 3d peak from the substrate (o) - calculation of the thickness of oxide films from the ratio of As 3d peak components connected with the oxide film and InAs substrate.

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