Model Monochromatic

A Surface Science Instruments SSX-100 spectrometer (model 206), equipped with an aluminum anode whose radiation was monochromatized (AlKa, 1486.6 eV) and focalized, was used. The positive charge developed at the surface of the samples was compensated with a charge neutralizer adjusted at an energy of 8 eV. 

As is well known, in the case of the hydrogen atom interacting with a monochromatic field, one-dimensional model provides an excellent description of the experimental chaotization thresholds for real three-dimensional hydrogen atom (Jensen, 1984). 

Figure 3.7 Comparison of the monochromatic Mo 3d XPS spectra of M0O3 in an insulating silica-supported catalyst and in a conducting, thin silica film-supported model catalyst, showing the effect of inhomogeneous charge broadening (courtesy of H. Korpik, Eindhoven).

All methods mentioned in Table 1 operate (typically) in the frequency domain a monochromatic optical wave is usually considered. Two basically different groups of modeling methods are currently used methods operating in the time domain, and those operating in the spectral domain. The transition between these two domains is generally mediated by the Fourier transform. The time-domain methods became very popular within last years because of their inherent simplicity and generality and due to vast increase in both the processor speed and the memory size of modem computers. The same computer code can be often used to solve many problems with rather... 

Ito, T. Saito, M. Kobayashi, K. Dissociation of a model DNA compound dApdA by monochromatic soft X-rays in solids and comments on the high selectivity for 3 breakage in the phosphoester bond. Int. J. Radiat. Biol. 1992, 62 (2), 129-136. 

We further address the influence of the pulse shape on the Sq S2 S process dynamics. For this purpose, simple pulse profiles are used in Ref. [42], shown in Figure 9.18, which can be modeled by analytical functions. More specifically, the profiles shown in the left panel of Figure 9.18 correspond to pulses composed from one, as pulse A, or three, as pulses B, C, and D, monochromatic pulses, as defined in Eqs (9.69) and (9.70). However, in all cases, the intensity and phase of each monochromatic pulse used in Eq. (9.69) is equal to 4TW/cm and zero, respectively. Moreover, the carrier frequencies of the monochromatic pulses are also the same in all cases, equal to 4.81 eV different carrier frequencies considered for profiles shown in the right part of Figure 9.18, are discussed below. The other parameters in Eqs. (9.69) and (9.70) regarding the pulses A, B, C, and D are as follows for pulse (A) with = 1, we have = 70 fs and = 24 fs for... 

Catalyst surface areas were measured using the multi-point BET method on a Carlo-Erba Ins. Sorpty 1750. Before the measurements, the samples were heated under dynamic vacuum at 573 K for 1 h in order to remove adsorbed water and impurities. Measurements were made at liquid nitrogen temperature with nitrogen as the adsorbate gas. Powder X-ray diffraction measurements were performed on a Siemens Model D-500 diffractometer with Co Kc monochromatic radiation (X = 1.78901 A) and the high resolution electron microscopy was carried out on a Topcon EM-002B microscope. To prevent artefacts no solvents were used in the preparation and mounting of samples for HRTEM. 

The position of a nickel Auger peak superimposed on the N(ls) photoelectron peak was detected when spectra of coated nickel samples were collected on the Physical Electronics Model 5300 ESCA system using Mg Ka X-rays. Therefore, XPS spectra of nickel samples were obtained using a Surface Science Instruments SSX-100-03 instrument equipped with a monochromatic A1 Ka source. The N(ls) high-resolution spectra obtained from polished nickel which had been coated with y-APS from a 1% aqueous solution at pH 10.4 are shown in Fig. 8. 

Figure 3.1 shows a simplified picture of an interface. It consists of a multilayer geometry where the surface layer of thickness d lies between two centrosymmetric media (1 and 2) which have two different linear dielectric constants e, and e2, respectively. When a monochromatic plane wave at frequency co is incident from medium 1, it induces a nonlinear source polarization in the surface layer and in the bulk of medium 2. This source polarization then radiates, and harmonic waves at 2 to emanate from the boundary in both the reflected and transmitted directions. In this model, medium 1 is assumed to be linear. 

Irradiation. The thick sheets were irradiated with monochromatic light according to ref. [2] using an Applied Photophysics Model 5350 photo-irradiator equipped with a 900 W short arc high pressure xenon lamp, a f/3.4 monochromator and an exit lens of quartz providing illumination over an area of 1.3 by 2.4 cm at a distance of 16 cm from the lens. The illumination was uniform over the central area (0.8 by 1.7 cm) which was analyzed. The entrance slit of die monochromator was kept at 5 nm and the exit slit at 10 nm to secure enough output energy. Irradiations were performed at ambient temperatures (ca. 23°Q in air. 

---