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Local additional interactions

Thus the alternative approach is to create enhancements (add-ons) to an ERP system that do not have their own persistent database and provide additional interactive functions, visualization and algorithmic processing of enhanced model data. The add-ons create a temporary local data storage (LiveCache) to effectively process the enhanced data. However, all data is stored persistently exclusively in the ERP system. This allows for the local LiveCache to use a mapping of the ERP data model that is structured in a way that is more suitable for APS purposes. Additionally the... [Pg.274]

We may perform the same analysis for the allyl radical and the allyl anion, respectively, by adding the energy of 4>2 to the cation with each successive addition of an electron, i.e., H (allyl radical) = 2(a + V2/3) + a and Hn allyl anion) = 2(a + s/2f) + 2a. In the hypothetical fully 7T-localized non-interacting system, each new electron would go into the non-interacting p orbital, also contributing each time a factor of a to the energy (by definition of o ). Thus, the Hiickel resonance energies of the allyl radical and the allyl anion are the same as for the allyl cation, namely, 0.83/1. [Pg.109]

On the other hand, there are several clear perspectives for future improvements and extensions of COSMO-RS. One of the most obvious perspectives is the improvement of the underlying quantum chemical methods. While density functional theory appears to have reached its limit regarding the quality of the electrostatics, and hence of the COSMO polarization charge densities, there will be an increase in the availability of higher correlated ab initio methods like coupled cluster calculations at affordable computational cost. Quantum chemical calculation of local polarizability and eventually of suitable descriptors for dispersion forces should provide additional information about the strength of local surface interactions and can be used to improve the various surface interaction functionals. At the other end, the quantum chemical COSMO calculations for larger biomolecules and enzymes, which have just become available at reasonable... [Pg.217]

A central issue is the number of different atom types that are used in a particular force field. There is always a compromise between increasing the number to allow for the inclusion of more environmental effects (i.e., local electronic interactions) vs. the increase in the number of parameters to be determined to adequately represent a new atom type. In general, the more subtypes of atoms (how many different kinds of nitrogen, for example), the less likely that the parameters for a particular application will be available in the force field. The extreme, of course, would be a special atom type for each kind of atomic environment in which the parameters were chosen, so that the calculated properties of each molecule would simply reproduce the experimental observations. One major assumption, therefore, is that the force constants (parameters) and equilibrium values of the equations are functions of a limited number of atom types and can be transferred from one molecular environment to another. This assumption holds reasonably well where one may be primarily interested in geometric issues, but is not so valid in molecular spectroscopy. This had led to the introduction of additional equations, the so-called "cross-terms" which allow additional parameters to account for correlations between bond lengths and bond angles... [Pg.80]

This decomposition suggests that at least in principle the //o-problem can be solved. The additional interaction Hamiltonian H (t) is assumed to be localized in time, i.e. //i ( r t — oo) = 0. The explicitly time-independent Hamiltonian Ho can be diagonalized through a proper definition of creation/annihilation operators a-s)f/a-s) corresponding to noninteracting particles of the species (s) and characterized by a set of quantum numbers denoted by a label i ... [Pg.2]

It should be noted that all the above interactions take place within the porous structure of the silica substrate, which might further favor certain interactions because of local confinement and additional interactions between surface-restrained ligands located at distant positions on the curved walls of the confining pores. Also, the alkanesiloxane-bonded chains are at a relatively low packing density and entropically confined compared to a bulk liquid and therefore solvation models assuming bulk liquid properties for the stationary phase should be interpreted with care [257]. [Pg.308]

The magnetic moment of the electron will also undergo additional interactions with local magnetic fields originating from non-zero nuclear spins. This coupling, known as the hyperfine interaction, is given by ... [Pg.298]


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See also in sourсe #XX -- [ Pg.298 ]




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