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Polarization continued functions

It is worth emphasising too, that the position of those lines representing equilibria with the dissolved species, M, depend critically on the solubility of the ion, which is a continuous function of pH. For example, iron in moderately alkaline solution is expected to be very passive and so it is in borate solutions (in the absence of aggressive ions). However, the anodic polarization curve still shows a small active loop at low potential. [Pg.135]

Formation of the reaction products, in the case of the methylene linker, was rationalized by means of density functional theory (DFT) calculations with the inclusion of a solvent effects polarized continuous model (PCM). The calculations... [Pg.48]

The charge density p of the solute may be expressed either as some continuous function of r or as discrete point charges, depending on the theoretical model used to represent the solute. The polarization energy, Gp, discussed above, is simply the difference in the work of charging the system in the gas phase and in solution. Thus, in order to compute the polarization free energy, all that is needed is the electrostatic potential in solution and in the gas phase (the latter may be regarded as a dielectric medium characterized by a dielectric constant of 1). [Pg.394]

Marchi and co-workers [27,28] have applied Equation (1.79) in the context of classical MD by using a Fourier pseudo-spectral approximation of the polarization vector field. This approach provides a convenient way to evaluate the required integrals over all volume at the price of introducing in the extended Lagrangian a set of polarization field variables all with the same fictitious mass. They also recognized the cmcial requirement that both the atomic charge distribution and the position-dependent dielectric constant be continuous functions of the atomic positions and they devised suitable expressions for both. [Pg.68]

The basic concept of micromagnetism is to replace the atomic magnetic moments by a continuous function of position. In a continuum theory the local direction of the magnetic moments may be described by the magnetic polarization vector... [Pg.103]

After ealeulating discrete values of frequency and relaxation time for the polarization mode and different wave veetors, a continuous function for the relaxation time and dispersion relations can be established for eaeh mode. The results shown in Fig. 3 are obtained with the Lennard-Jones potential for Argon. An approach similar to that described above can be applied with the Stillinger-Weber potential for silieon. [Pg.388]

Let us continue using N2 as an example for how one usually varies the box within which the anion is constrained. One uses a conventional atomic orbital basis set that likely includes s and p functions on each N atom, perhaps some polarization d functions and some conventional diffuse s and p orbitals on each N atom. These basis orbitals serve primarily to describe the motions of the electrons within the usual valence regions of space. To this basis, one appends an extra set of diffuse ir-symmetry orbitals. These orbitals could be p j (and maybe d ) functions centered on each nitrogen atom, or they could be orbitals centered at the midpoint of the N-N bond. Either choice can be used because one only needs a basis capable of describing the large-r L = 2 character of the metastable Ilg state s wave function. One usually would not add just one such function rather several such functions, each with an orbital exponent aj that characterizes its radial extent, would be used. Let us assume, for example, that K such additional diffuse tt functions have been used. [Pg.458]

EOs are generally products of rather complex compositions used contemporaneously in aroma therapy and for centuries as aromatic medicinal plant species in traditional systems of medicine. Aromatic formulas are used for the treatment of a variety of illnesses, including those that affect the CNS (Almeida et al. 2004). Volatile compounds presenting sedative or stimulatory properties have been and continue to be identi ed in EOs from aromatic medicinal species spread into dif ferent families and genera. The majority of these substances have small structures with less than 12 carbons and present low-polarity chemical functions, being therefore quite volatile. Since most natural EOs are formed by complex mixtures, their bioactivity(ies) is obviously dependent on the contribution of their various components. Therefore, studies failing to characterize at least the main components of the EO studied are not discussed in this chapter. [Pg.363]

The degree of bond polarity is a continuous function. The guidelines given here are approximate. [Pg.342]

For the case of Ag it was found that both anodic and cathodic polarization lead to the creation of small insulated particles on the YSZ surface. Both the Fermi level and the work function of the insulated Ag particles was found to change with Ag electrode overpotential but the changes are smaller than on the continuous Ag film.24... [Pg.256]


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See also in sourсe #XX -- [ Pg.372 , Pg.373 , Pg.462 ]




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Polarity function

Polarization continued)

Polarization functions

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