Electron comparison with other methods

This kind of estimation of the relative concentration is the most widely used method for quantitative EELS analysis. It is advantageous because the dependence on the primary electron current, Iq, is cancelled out this is not easily determined in a transmission electron microscope under suitable analytical conditions. Eurthermore, in comparison with other methods, e. g. Auger electron spectroscopy and energy-disper-... 

In comparison with other methods for determining molecular geometry, such as spectroscopy (1.2.1) and X-ray crystahography, the merits of gas electron diffraction are the following ... 

We continue this review with a discussion of local aromaticities estimated by EC values in comparison with other methods. Among the many pubhshed approaches to this problem, pioneered by Oskar Polansky (Polansky and Derflinger 1967 Monev et al. 1981) which were presented in Part 6 of our series, entitled Partitioning of u-electrons in rings of polycyclic conjugated hydrocarbons. 

A. T. Balaban and M. Randic, Partitioning of jc-electrons in rings of polycyclic conjugated hydrocarbons Part 6. Comparison with other methods for estimating the local aromaticity of rings in polycyclic benzenoids, J. Math. Chem. 37 (2005) 443-453. 

K Fe(CN)6 oxidation Compound F is stoichiometrically inactivated by oxidation with K.3Fe(CN)6 (Shimomura and Johnson, 1967) thus, it is possible to estimate the molecular extinction coefficient (e) of the 388-390 nm absorption peak by titrating F with K.3Fe(CN)6- The e value obtained by the titration in 50% ethanol was 15,400 (assuming the reaction to be one-electron oxidation) or 30,800 (assuming two-electron oxidation). Two other methods of lesser precision were used to determine the true s value 1) the dry weight of the ethyl acetate extract of an acidified solution of F gave an e value of 14,100 2) the comparison of NMR signal intensities gave a value of 11,400 2,000 in water (H. Nakamura, Y. Oba, and A. Murai, 1995, personal... 

Car-C.i = 1.52 A. and C -C = 1.37 A., these distances being 0.02 A. smaller than those given by our photographs. The rings given by mesitylene and hexamethylbenzene are unusually sharp and well defined, and we estimate, by comparison with other substances for which the electron-diffraction method has been tested,81 that the error in our values of sa is not greater than about 0.5%. 

There have been a few VB calculations on this molecule, particularly since the recent advances in computer capability make the problem of non-orthogonality of the orbitals less serious. Maclagan and Schnuelle384 have reported the results of a minimal-basis STO calculation, including all configurations which do not involve excitation of the Be core electrons. Comparison with a MO calculation was made. A VB equivalent to the CNDO/2 method was proposed. Gallup et a/.385 have also carried out a similar calculation and proposed a population analysis scheme for VB wavefunctions. Other calculations on BeKfe by these workers have appeared.116-118... 

Another characteristic of electron diffraction in comparison with other diffraction methods is multiple scattering. The interaction between the electron beam... 

When comparing results with other methods it is often necessary to dilute the suspensions without changing their state of agglomeration. Despite this, under electrokinetically stable conditions, excellent agreement was found in a comparison with the Mastersizer S, the Ultra Fine Particle Analyzer, the Sedigraph 5000D and scanning electron microscopy [265]. It was stressed however that sample preparation procedure was important. 

The redox potentials of short-lived silver clusters have been determined through kinetics methods using reference systems. Depending on their nuclearity, the clusters change behavior from electron donor to electron acceptor, the threshold being controlled by the reference system potential. Bielectronic systems are often used as electron donors in chemistry. When the process is controlled by critical conditions as for clusters, the successive steps of monoelectronic transfer (and not the overall potential), of which only one determines the threshold of autocatalytical electron transfer (or of development) must be separately considered. The present results provide the nuclearity dependence of the silver cluster redox potential in solution close to the transition between the mesoscopic phase and the bulk metal-like phase. A comparison with other literature data allows emphasis on the influence of strong interaction of the environment (surfactant, ligand, or support) on the cluster redox potential and kinetics. Rela-... 

We review the Douglas-Kroll-Hess (DKH) approach to relativistic density functional calculations for molecular systems, also in comparison with other two-component approaches and four-component relativistic quantum chemistry methods. The scalar relativistic variant of the DKH method of solving the Dirac-Kohn-Sham problem is an efficient procedure for treating compounds of heavy elements including such complex systems as transition metal clusters, adsorption complexes, and solvated actinide compounds. This method allows routine ad-electron density functional calculations on heavy-element compounds and provides a reliable alternative to the popular approximate strategy based on relativistic effective core potentials. We discuss recent method development aimed at an efficient treatment of spin-orbit interaction in the DKH approach as well as calculations of g tensors. Comparison with results of four-component methods for small molecules reveals that, for many application problems, a two-component treatment of spin-orbit interaction can be competitive with these more precise procedures. 

In the case of actinyls, where no experimental information on unperturbed gas phase species is available, the assessments were mainly based on a comparison with other computational results, first of all, with the HF-based correlation methods, such as ACPF or CCSD(T), either at the all-electron or relativistic... 

The quantum mechanical many-body nature of the interatomic forces is taken into account naturally through the Hellmann-Feynman theorem. Since the scheme usually uses a minimal basis set for the electronic structure calculation and the Hamiltonian matrix elements are parametrized, large numbers of atoms can be tackled within the present computer capabilities. One of the distinctive features of this scheme in comparison with other empirical schemes is that all the parameters in the model can be obtained theoretically. It is therefore very useful for studying novel materials where experimental data are not readily available. The scheme has been demonstrated to be a powerful method for studying various structural, dynamical, and electronic properties of covalent systems. 

Both geometric and electronic effects from the underlying substrate create shifts in the d-band center of the core-shell electrocatalyst compared to Pt only, which influence the activity for the ORR. The Pt monolayer deposition via Cu UPD displacement is described in the next section in comparison with other core-shell preparation methods. 

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