Band width, spectral

Band intensities spectral, 249 selection rules, 244 Band widths spectral, 246 temperature effects, 248 Barium, pentakis(diacetamide)-stereochemistry, 99 Bathocuproine absorptiometry, 550 Bathophenanthroline absorptiometry, 550... 

X EFFECTIVE BAND WIDTH = SPECTRAL SLIT WIDTH... 

Although the power spectral density contains information about the surface roughness, it is often convenient to describe the surface roughness in terms of a single number or quantity. The most commonly used surface-finish parameter is the root-mean-squared (rms) roughness a. The rms roughness is given in terms of the instrument s band width and modulation transfer function, M(p, q) as... 

Table 4.1. Various processes contributing to the spectral line broadening for local vibrations. Frequencies of collectivized local vibrations QK (solid arrows) are supposed to exceed phonon frequencies oiRq (dashed arrows) Ok > max oncq. For an extremely narrow band of local vibrations, diagrams A and B respectively refer to relaxation and dephasing processes, whereas diagrams C account for the case realizable only at the nonzero band width for local vibrations.

Lead line, 217nm lamp current, 8mA spectral band width, 0.7nm scale expansion 4x (0.25A full scale) furnace gas, 135ml H min 1. The deuterium background corrector was used. 2... 

Little is known about the fluorescence of the chla spectral forms. It was recently suggested, on the basis of gaussian curve analysis combined with band calculations, that each of the spectral forms of PSII antenna has a separate emission, with Stokes shifts between 2nm and 3nm [133]. These values are much smaller than those for chla in non-polar solvents (6-8 nm). This is due to the narrow band widths of the spectral forms, as the shift is determined by the absorption band width for thermally relaxed excited states [157]. The fluorescence rate constants are expected to be rather similar for the different forms as their gaussian band widths are similar [71], It is thought that the fluorescence yields are also probably rather similar as the emission of the sj tral forms is closely approximated by a Boltzmann distribution at room temperature for both LHCII and total PSII antenna [71, 133]. 

Figure 10.10 shows the experimental system of TE-CARS microscopy (Ichimura et al. 2004a). As similar to the TERS system (Hayazawa et al. 2000), the system mainly consists of an excitation laser, an inverted microscope, an AFM using a silver-coated probe, and a monochromator. Two mode-locked Ti sapphire lasers (pulse duration 5 picoseconds [ps] spectral band width 4 cm- repetition rate 80 MHz) are used for the excitation of CARS. The (o and (O2 beams are collinearly combined in time and space, and introduced into the microscope with an oil-immersion objective lens (NA = 1.4) focused onto the sample surface. As the z-polarized component of the... 

In experimental measurements, such sharp 8-function peaks are, of course, not observed. Even when very narrow band width laser light sources are used (i.e., for which g(co) is an extremely narrowly peaked function), spectral lines are found to possess finite widths. Let us now discuss several sources of line broadening, some of which will relate to deviations from the "unhindered" rotational motion model introduced above. 

The pump and probe pulses employed may be subjected to a variety of nonlinear optical mixing processes they may be prepared and characterized by intensity, duration, spectral band width, and polarization. They may arrive in the reaction chamber at a desired time difference, or none. The probe pulse may lead to ionizations followed by detections of ions by mass spectrometry, but many alternatives for probing and detection have been used, such as laser-induced fluorescence, photoelectron spectroscopic detection, absorption spectroscopy, and the like. 

A third example can be taken from analytical chemistry. Absorption and resonance Raman spectra of phenol blue were measured in liquid and supercritical solvents to determine the solvent dependence of absorption bandwidth and spectral shifts. Good correlation between absorption peak shift and resonance Raman bands and between Raman bands and bandwidth of C-N stretching mode were observed while anomalous solvent effect on the absorption bandwidth occnrred in liquid solvents. Large band-widths of absorption and resonance Raman spectra were seen in supercritical solvents as compared to liquid solvents. This was dne to the small refractive indices of the supercritical solvents. The large refractive index of the liqnid solvents only make the absorption peak shifts withont broadening the absorption spectra (Yamaguchi et al., 1997). 

The calculation of the core levels of LajCuO discussed above was performed within the cluster approximation wherein the dependence of the spectral shape on the oxygen band-width is missed out. In order to include the effect of the oxygen 2p derived band on the spectral shape, the core-level photoemission calculation has to be performed within the impurity model which includes the O 2p band-width (instead of a single O 2p level). For reasonable values of the hybridization strength, t, the range of values of A is such that the Cu appears close to the bottom of the... 

It is interesting to note that if these spectral data are assumed to arise from four-coordinated SbO and BiO species, then the effective increase in m yields ry values of around 60,000 cm for Sb (III) and 70,000 cm" for Bi(III)—values that are significantly closer to the experimental free ion frequencies. The existence of a (coordinated) SbO or BiO ion would also explain the greater band width observed for the Sq absorption which occurs with Sb (III) and Bi (III), since the lower sym-... 

By dealing with metal ions with different configurations this paper will illustrate the dependence of the spectral band shape on the nature of the metal ion. This, however, is a well-known and reasonably well understood phenomenon. By dealing with a given ion in different host lattices we will illustrate how the spectral band width depends on the nature of the host lattice. This dependence is of a larger complexity. 

The structure of this review is as follows. In Chap. 2 we will survey shortly and nonmathematically the theories in use to explain spectral band width and structure. In subsequent chapters we will deal with a couple of different metal... 

Fig. 17a and b. Spectral distribution of fluorescence energy in the visible region, a) AJginite in Permian Boghead coal, b) Huronispora in Gunfiint chert. Irradiation at 365 nm, band width 10 on, field of measurement 5 pm diam. Courtesy of Zeiss Laboratories... 

Figure 4-30 A Raman spectrum of BaTi03 for Ba/Ti = 0.9999 with spectral parameters (intensities and half-band width) defined. This sample was quenched after 3 hours in 1 atm oxygen. (Reproduced with permission from Ref. 51.)...

In the last two sections we analyzed spectral and relaxation properties of 3D and 2D strong dipolar excitons in high-quality crystals at low temperatures in terms of the strong excitonic coherence of band width 500 cm l, preserving the properties of the quasi-ideal crystal structure (what we called the intrinsic surface-bulk system) in the presence of weak disorder A... 

Figure 19 shows the results on apamin and scyllatoxin (30). Owing to the larger size of these peptides, the different amide I states underneath the amide I band are no longer spectrally resolved, so that the absorption spectrum appears as a broad band (width 30-40 cm ) with only very... 

Element Wavelength (nm) Spectral band-width (nm) Lamp current (mA) Sensitivity (ppm/1% absorption) This work Jaworowski Van Loon et al. et al. ... 

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