Line-shape studies Gaussian

The linewidth, or lineshape, is the third aspect of the ESR spectrum important in any study of radicals. The two most frequently encountered lineshapes observed are the Lorentzian and Gaussian. The Gaussian line-shape is observed when the line is the superposition of a large number of unresolved individual components, such a line being referred to as inho-mogeneously broadened. More important is the Lorentzian lineshape which is often observed for radicals in solution, when complications due to unresolved hyperfine splittings do not occur. The Lorentzian lineshape may be defined by... 

Silk. Structural studies of the model peptides of Bombyx mori silk-elastin like protein were undertaken using solid state NMR. Detailed structural analyses were performed using deconvolution subroutines assuming Gaussian line shapes for the Ala peaks. 

Fourier transform is in face the line shape one would observe directly in an actual resonance experiment. The width of the line corresponds to I/T2, where T2 is the characteristic transverse relaxation time. In many instances Gx(t) can be written as a simple exponential relaxation Gx(t) = expC-t/Tp), corresponding to a Lorentzian line shape. However, more complicated functional forms (the next simplest being Gaussian) are often used to fit the data, particularly in studies of/i diffusion and trapping in solids. 

The results in Table 8 indicate that the chemical effect on the KP/Ka ratios is in order of several %. This means that the experimental studies on this effect should be made very carefully. In all experiments except for two, Paci-Mazzilli and Urch [20] and Mukoyama et al [26], Si(Li) detectors were used to observe x-ray spectra. Owing to poor energy resolution of the solid-state detectors, K(3 satellite peaks cannot be resolved from the K 3, z diagram line and the presence of these peaks should be taken into account in the data analysis of the experimental spectra. However, a single Gaussian shape has often been used for the Kf3 composite peak in most experiments. In order to compare with the present theoretical values, it is hoped that more systematic studies for the chemical effect on the K /Ka ratios for 3d elements be performed with high... 

Early studies (Reimer et al., 1980) indicated a broad Gaussian component superimposed on a narrower Gaussian, but most recent studies (Reimer et al., 198 lb Carlos and Taylor, 1980,1982b Taylor and Carlos, 1980 Jefirey and Lowry, 1981) suggest that the narrow line has a Lorentzian shape. Microcrystalline films of Si H also exhibit a broad Gaussian superimposed on a narrower Lorentzian line (Kumeda et al., 1983). This fact demonstrates that the microstructure that gives rise to the two different sites exists in both the crystalline and amorphous forms. All studies confirm that the widths of the two lines are governed by the dipolar term [Eq. (3)] in the Hamiltonian. 

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