Spectrum distortions

The spectrum distortion introduced by all such filters limits the spectrometer s scanning rate. The subtleties of the scan rate s dependence on electrical filtering and slit width for constant signal-to-noise ratio are explored by Blass and Halsey (1981). 

Fig. 17. Delayed fluorescence spectrum of 5 X 10-63/ anthracene in ethanol.84 Half-bandwidth of analyzing monochromator was 0.05 ju-1 at 2.5 n K Intensity of exciting light was approximately 1.4 X 10 einstein cm. a sec.-1 at 2.73m-1 (366 mju). (1) Normal fluorescence spectrum (distorted by self-absorption). (2) Delayed emission spectrum at sensitivity 260 times greater than for curve 1. (3) Spectral sensitivity of instrument (units of quanta and frequency).

The most important parameter of the detection system is its response function. We have studied this extensively in Monte Carlo and other calculations. The calculated time-spectrum response to monoenergetic neutrons is composed of a Gaussian timing curve (2.97-ns FWHM), a trapezoidal contribution from detector thickness and non-axial paths, and an exponential tail, calculated by Monte Carlo, from multiple scattering in the neutron scintillator. (Spectrum distortion due to neutrons multiply scattered by structural and other parts of the apparatus and arriving at the neutron... 

Spectrum distortions such as baseline roll or phase distortions should be negligible. However no pulse sequence is ideal and as discussed in the following Check its there... 

The presence of water disrupts the absorption spectrum of protoporphyrin IX as it can be seen in figure 9.8a and b where absorption spectra are displayed in pure dioxane and in a solvent of 70% dioxane-30% water. The spectrum distortion is the result of porphyrin aggregation by water. 

Spectrum distortions in the in situ ATR spectra measured in Otto s configuration with a nonmetalic substrate are discussed in Ref. [61b]. 

Based on the ab initio theory of complex electronic ground state of superconductors, it can be concluded that e-p coupling in superconductors induces the temperature-dependent electronic structure instability related to fluctuation of analytic critical point (ACP - maximum, minimum or saddle point of dispersion) of some band across FL, which results in breakdown of the adiabatic BOA. When ACP approaches FL, chemical potential Pad is substantially reduced to IJ-antiadilJ-ad > Pantiad < b(o). Under these circumstances the system is stabilized, due to the effect of nuclear dynamics, in the antiadiabatic state at broken symmetry with a gap in one-particle spectrum. Distorted nuclear structure, which is related to couple of nuclei in the phonon mode r that induces transition into antiadiabatic state, has fluxional character. It has been shown that until system remains in antiadiabatic state, nonadiabatic polaron - renormalized phonon interactions are... 

In the linear approximation there is a direct Fourier relationship between the FID and the spectrum and, in the great majority of experunents, the spectrum is produced by Fourier transfonnation of the FID. It is a tacit assumption that everything behaves in a linear fashion with, for example, imifonn excitation (or effective RF field) across the spectrum. For many cases this situation is closely approximated but distortions may occur for some of the broad lines that may be encountered in solids. The power spectrum P(v) of a pulse applied at Vq is given by a smc fiinction 18]... 

The electronic spectrum of the radical has been recorded long before a satisfactory theoretical explanation could be provided. It was realized early on that the system should be Jahn-Teller distorted from the perfect pentagon symmetry (D5/, point group). Recently, an extensive experimental study of the high-resolution UV spectrum was reported [76], and analyzed using Jahn-Teller formalism [73],... 

The final term of Equation (6) corrects for the distortion of the ERS spectrum caused by velocity-dependent energy losses as the H ions pass through the stopper foil. 

Eg term. A magnetic moment of around 5.5 BM (i.e. 4.90 BM- -orbital contribution) is expected for pure octahedral symmetry but, in practice, distortions produce values in the range 5.2-5.4BM. Similarly, in the electronic spectrum, the expected single band due to the Eg t ge g) T2g t ge ) transition is broadened... 

The complex ion (Figure 2.32) contains Rh2 bound cis to two phosphorus atoms (2.216 A) and more distantly to four oxygens (2.201—2.398 A), exhibiting a distortion ascribed to the Jahn-Teller effect it is paramagnetic (fi = 1.80 fiB) and exhibits an ESR spectrum (Figure 2.33) showing rhodium hyperfine coupling as the doublet for g. ... 

M(NO)2(PPh3)2]+. The coordination number of the metal in both is four, in a distorted tetrahedral geometry. The position of i/(N—O) in the IR spectrum is essentially the same, and the rhodium and iridium compounds have similar slight bending of the M—N—O linkage. 

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