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Calculations differentiation

Because the semiclassical theories can be used to calculate differential cross sections with relative ease for close collisions between the incident charged particle and the bound electron, and the Bethe theory provides a straightforward method to describe low-energy electrons ejected in distant collisions, it is only natural to combine the best characteristics of the two approaches to derive a comprehensive description of electron impact ionization. [Pg.48]

Fig. 112. (Top) Polymer channel waveguide for optical gain. (Bottom) Calculated differential optical gain for an Er-doped devices (organic complex, 2x1 pm2 core section) as a function of pump power for direct (—) and ligand (—) excitation reproduced with permission from (SloolFet al., 2002). Fig. 112. (Top) Polymer channel waveguide for optical gain. (Bottom) Calculated differential optical gain for an Er-doped devices (organic complex, 2x1 pm2 core section) as a function of pump power for direct (—) and ligand (—) excitation reproduced with permission from (SloolFet al., 2002).
The main difference between the new potential and that of Buck et al., i.e. the depth of potential wells, cannot be verified by this high energy scattering calculation in order to provide major insights, work is in progress to compute the MO-VB PES at a higher level of theory and to calculate differential cross-sections at the lower collision energy of 275 cm 1 [69], where total inelastic and some state resolved differential cross sections are available [65]. [Pg.341]

From our krypton adsorption data, we must conclude that the adsorption energetics are the same within experimental error on all three mica samples for the range 0.2 <0< 0.8 (with the possible exception of the barium muscovite up to 0 0.4, as noted above). We have calculated differential heats and entropies... [Pg.271]

Table 6. Calculated differential Coulomb binding energy shifts due to change of valence s and d count in Tia)... Table 6. Calculated differential Coulomb binding energy shifts due to change of valence s and d count in Tia)...
It has been realized recently that the parameter O is of importance in calculating differential scattering. This, in turn, stimulated calculation of for the earliest model of nonadiabatic coupling, the Landau-Zener-Stueckel-berg model [28-30]. The model is formulated for a Hamiltonian with AH linear in R ... [Pg.331]

The existence of a common momentum profile for the manifold a confirms the weak-coupling binary-encounter approximation. Within these approximations we must make further approximations to calculate differential cross sections. For the probe amplitude of (11.1) we may make, for example, the distorted-wave impulse approximation (11.3). This enables us to identify a normalised experimental orbital for the manifold. If normalised experimental orbitals are used to calculate the differential cross sections for two different manifolds within experimental error this confirms the whole approximation to this stage. An orbital approximation for the target structure (such as Hartree—Fock or Dirac—Fock) is confirmed if the experimental orbital energy agrees with the calculated orbital energy and if it correctly predicts differential cross sections. [Pg.294]

Figure 2 Overlay of MALDI TOF spectra and the calculated differential number weight distributions obtained via SEC analysis ofpolv(dimethylsiloxane)s I, II and III M (SEC) =1920, 5000, 10900 (SEC) =2470. 5920. 12700 M (MALDI TOF) =1290, 2720, 5350, M , (MALDI TOF) = 1460. 2890, 5530 g mol- respectively... Figure 2 Overlay of MALDI TOF spectra and the calculated differential number weight distributions obtained via SEC analysis ofpolv(dimethylsiloxane)s I, II and III M (SEC) =1920, 5000, 10900 (SEC) =2470. 5920. 12700 M (MALDI TOF) =1290, 2720, 5350, M , (MALDI TOF) = 1460. 2890, 5530 g mol- respectively...
Fig. 13.5 DFT-calculated differential segregation energies are plotted as a function of Sn surface coverage, i.e., the concentration of Sn in the top layer of the Ni slab. The sohd square represents the energy required to transfer a Sn atom from the bulk of Ni to the bulk of Sn... Fig. 13.5 DFT-calculated differential segregation energies are plotted as a function of Sn surface coverage, i.e., the concentration of Sn in the top layer of the Ni slab. The sohd square represents the energy required to transfer a Sn atom from the bulk of Ni to the bulk of Sn...
Zare tmd co-workers [89] have measured differential cross sections for the Cl - -CH4(i 3fc = 0) -i HCl(iv = 0,j) + CH3 and Cl + CH4(ei(> = 1) HCl(i/ = 0/1,j) + CH3 reactions, at tm average translational energy of 0.159 elL Here is a stretch motion of H-CH3 and j is the HCl rotational quantum number. In order to compcU c with these exj)erimental results, we have calculated differential cross sections at this collision energy. Since the HCl rotational degree of freedom is not treated in the RBU model, we compare with the experimenttil results for j = 0. [Pg.273]

The numerical results for nine cases of the surface resistances are shown in Figure 6. It shows that the whole potential is high when the surface resistance is high. The maximum voltage of the sidelobe of the optional anode is 0.005 [V], Thirdly, the surface resistance was estimated by minimizing the residual function Eqn. (16). The residual function consists of three residuals between measurement and calculated differential potential at the depth of seven meters. The minimization was performed with the brute-force search. [Pg.86]

Fig. 1. Electron energy loss spectrum of propane (thin line) and the calculated spectrum (thick line) for the incident electron energy of 10 eV and the scattering angle of 100°. The bars at the bottom of the figure stand for the calculated differential cross sections. Fig. 1. Electron energy loss spectrum of propane (thin line) and the calculated spectrum (thick line) for the incident electron energy of 10 eV and the scattering angle of 100°. The bars at the bottom of the figure stand for the calculated differential cross sections.
Difference point in extraction calculations Differential contactors Diffuse wave Diffusion... [Pg.1008]

In numerical calculations, differentials are not of direct use, since they are smaller than any finite quantities that you can specify. Their use lies in the construction of formulas, especially through the process of integration, in which infinitely many infinitesimal quantities are added up to produce something finite. We discuss integration in the next chapter. [Pg.104]

More recently, Karplus and Raff [39] have carried out extensive computer experiments for the reaction between K and CH3I and have found that the dimensionality of the calculation and the details of the potential are of critical importance for some considerations. They used a potential energy function similar to that employed by Blais and Bunker and calculated both two- and three-dimensional classical trajectories. As usual, the initial conditions were selected by use of a Monte Carlo procedure, and the trajectories were examined to see if reaction occurs. In both dimensions, most of the reaction energy appears as internal excitation of products. The calculated differential cross sections are markedly different for two and three dimensions and both disagree with the molecular beam experiments. The total reaction cross section obtained from the computer calculations is about 400 in both two and three dimensions, as compared to the experimental result of about 10 A. Karplus and Raff found the situation could be greatly improved by... [Pg.129]

An analysis of the kinetic curves of the pigments samples sedimentation has been done in accordance with the method [5]. Calculated differential curves of particles aggregates distribution per sizes in water and butyl acetate are represented on Fig. 4. [Pg.250]

The dlstorted wave Born-approximation (DWBA) is a quantum technique for calculating differential cross sections, integral cross sections and product state distributions for three dimensional (3D) chemical reactions of the type... [Pg.247]


See other pages where Calculations differentiation is mentioned: [Pg.72]    [Pg.438]    [Pg.344]    [Pg.109]    [Pg.392]    [Pg.127]    [Pg.296]    [Pg.63]    [Pg.131]    [Pg.431]    [Pg.642]    [Pg.210]    [Pg.282]    [Pg.274]    [Pg.343]    [Pg.378]    [Pg.316]    [Pg.316]    [Pg.476]    [Pg.85]    [Pg.274]    [Pg.343]    [Pg.136]    [Pg.130]    [Pg.115]    [Pg.315]    [Pg.72]   
See also in sourсe #XX -- [ Pg.711 , Pg.712 ]




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