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Constant self-energy

If the solute were simply a collection of point charges surrounded by a continuous dielectric medium with the bulk dielectric constant of the solvent, the self-energy and the strength of charge-charge interactions in the solute would be reduced by a factor of . This is called dielectric screening. However, the solute itself occupies a finite volume, and solvent is excluded from this volume. This reduces the dielectric screening and is called... [Pg.80]

Spiering et al. (1982) have developed a model where the high-spin and low-spin states of the complex are treated as hard spheres of volume and respectively and the crystal is taken as an isotropic elastic medium characterized by bulk modulus and Poisson constant. The complex is regarded as an inelastic inclusion embedded in spherical volume V. The decrease in the elastic self-energy of the incompressible sphere in an expanding crystal leads to a deviation of the high-spin fraction from the Boltzmann population. Pressure and temperature effects on spin-state transitions in Fe(II) complexes have been explained based on such models (Usha et al., 1985). [Pg.203]

What is the Born solvation energy of Fe3+ in water having a dielectric constant of 78, and what is its value when it is in ethanol, which has dielectric constant of 36 (b) What is the self-energy of Fe3+ in a vacuum (c) Is there any meaningful difference between the Born solvation energy and the self-energy of an Fe3+ ion The radius of this ion is 0.64 A and the diameter of water is 2.76 A. (c) Where do you think there is a possible flaw in Born s solvation equation (Khan)... [Pg.815]

The subscripts i which have been added refer to the different species of ion-dipoles, and the symbols ax(D),... indicate that the respective coefficients have to be calculated with the value of D and n2. From the way our work function A has been derived, it is evident that it contains the contributions which are caused by the presence of the solutes and by the change in dielectric constant of the solvent. The contributions which result from the first term in Equation 19 and which represent the work which is required to build up the ion-dipole in a standard environment (e.g., a vacuum) have disappeared from Equation 24 (being identical in A and A o). This self-energy of the particles is without interest for the present investigation and depends, of course, in a decisive way on the underlying model. [Pg.325]

It will be useful to express the self-energy of the polaron in the two models in units of a dimensionless coupling constant which is considerably important in polaron theory ... [Pg.27]

Im. Z i(E) can be considered as a product of an ionic excitation density of states and an energy-dependent coupling constant. In model calculations one can independently vary the shape and the band with of the denstiy of states and the strength of the coupling constant. In the present case we can only vary these parameters indirectly by changing the atomic number Z. Since the self-energy involves the polarizability of the ionic system there must be an oscillator-strength sum rule such that... [Pg.50]

Other ions in the solution. The self-energy of a dipole embedded in a dielectric sphere is the key to Onsager s theory of the dielectric constant of dipolar fluids. Equally, in any theory for, say, the surface energy of water, or adsorption of molecule, the self-energy of a molecule as a function of its distance from an interface is involved. In adsorption proper, the same selfenergy for a molecule appears in the partition function of statistical mechaiucs from which the adsorption isotherm is derived. [Pg.90]

Increasing Q, would decrease the average minimum distance between a self localized PFq.fast excitation and a possible CTS defect, which suggests that Eq. 4, simply describes the qualitative dependence with distance for the Dexter electron exchange mechanism k j = ko e R, where ko is the maximum rate constant for energy transfer, occurring when donor and acceptor are at the collision distance Ro and R is the separation between donor and acceptor when they are further apart than Ro. [Pg.209]

The self-energy of the right electrode is similarly defined. How to define the lesser (greater) self-energy, which represents the scatter-in (out) function ofelectrons provided by electrodes, is the central issue. Practical applications of the NEGF will be possible if the (generalized) Kadanoff-Baym ansatz is applicable [67-69, 77]. In the E-M-E system under constant bias Vb, electrodes are the electron reservoirs by means of the Landauer picture thus they can be approximated as a non-interacting quasi-equilibrium system,... [Pg.85]

Finally, the self-part of the dipolar Ewald energy, U, cannot be derived by applying the Nabla operator as for the other terms, because the corresponding self-term for charged systems is already a constant. Specifically, one realizes from Eq. (6.17b) that the Coulomb self-energy can be rewritten as... [Pg.312]


See other pages where Constant self-energy is mentioned: [Pg.77]    [Pg.109]    [Pg.117]    [Pg.77]    [Pg.109]    [Pg.117]    [Pg.178]    [Pg.67]    [Pg.453]    [Pg.91]    [Pg.135]    [Pg.39]    [Pg.285]    [Pg.286]    [Pg.15]    [Pg.18]    [Pg.53]    [Pg.319]    [Pg.160]    [Pg.316]    [Pg.397]    [Pg.107]    [Pg.688]    [Pg.315]    [Pg.169]    [Pg.52]    [Pg.197]    [Pg.114]    [Pg.129]    [Pg.160]    [Pg.15]    [Pg.198]    [Pg.15]    [Pg.247]    [Pg.688]    [Pg.567]    [Pg.143]    [Pg.213]    [Pg.203]    [Pg.82]    [Pg.93]    [Pg.101]   
See also in sourсe #XX -- [ Pg.117 , Pg.118 ]




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Constant energy

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