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Electric field, calculation effect

The excess contribution is due to the distribution of the valence electrons over the energy levels, and includes the splitting of the ground term by the crystalline electric field (Stark effect) and is called the Schottky heat capacity or Schottky anomaly. It can be calculated from... [Pg.154]

The study of the electric field strength effect on the shape of the density gradient formed in the TLF cell indicated an important difference compared with the first approximation theoretical model. A series of experimental data and the theoretically calculated curves are shown in Figure 6. The difference can be caused by the interactions between the colloidal particles of the binary density forming carrier liquid. Moreover, the electric field strength across the cell or channel thickness was estimated from the electric potential measured between the electrodes, but the electrochemical processes at both electrodes can contribute to this difference. [Pg.34]

In order to calculate the effect quantitatively, explicit expressions are needed for the complex dielectric constant, e, in the presence and absence of an electric field the effects of thermal broadening and inhomogeneities in the electric field may be included at a later point in the theoretical development. [Pg.393]

A number of types of calculations can be performed. These include optimization of geometry, transition structure optimization, frequency calculation, and IRC calculation. It is also possible to compute electronic excited states using the TDDFT method. Solvation effects can be included using the COSMO method. Electric fields and point charges may be included in the calculation. Relativistic density functional calculations can be run using the ZORA method or the Pauli Hamiltonian. The program authors recommend using the ZORA method. [Pg.333]

Now the effective conductivity ia the direction of the electric field is <7/(1 + /5 ), ie, the scalar conductivity reduced by a factor of (1 + /5 ) by the magnetic field. Also, the electric current no longer flows in the direction of the electric field a component j exists which is perpendicular to both the electric and magnetic fields. This is the Hall current. The conductivity in the direction of the Hall current is greater by a factor of P than the conductivity in the direction of the electric field. The calculation of the scalar conductivity starts from its definition ... [Pg.419]

A finite time is required to reestabUsh the ion atmosphere at any new location. Thus the ion atmosphere produces a drag on the ions in motion and restricts their freedom of movement. This is termed a relaxation effect. When a negative ion moves under the influence of an electric field, it travels against the flow of positive ions and solvent moving in the opposite direction. This is termed an electrophoretic effect. The Debye-Huckel theory combines both effects to calculate the behavior of electrolytes. The theory predicts the behavior of dilute (<0.05 molal) solutions but does not portray accurately the behavior of concentrated solutions found in practical batteries. [Pg.509]

Fig. 6. Calculated optical absorption spectra of a metallic CNT in a magnetic flux. In the case that the electric field is parallel to the axis (left), the absorption exhibits a distinct AB effect. In the case of the perpendicular polarisation (right) the depolarisation effect suppresses the absorption almost completely. Fig. 6. Calculated optical absorption spectra of a metallic CNT in a magnetic flux. In the case that the electric field is parallel to the axis (left), the absorption exhibits a distinct AB effect. In the case of the perpendicular polarisation (right) the depolarisation effect suppresses the absorption almost completely.
This is not an SCRF model, as the dipole moment and stabilization are not calculated in a self-consistent way. When the back-polarization of the medium is taken into account, the dipole moment changes, depending on how polarizable the molecule is. Taking only the first-order effect into account, the stabilization becomes (a is the molecular polarizability, the first-order change in the dipole moment with respect to an electric field, Section 10.1.1). [Pg.395]

However, the effective internal electric field in the device deviates from the field calculated using Eq. (9.10) due to the internally built-in field (see above) because of defect charging in the active layer [55] and interface effects [57],... [Pg.156]

Eckart, criteria, 264, 298 procedure, 267 Effective charge, 274, 276 Effective Hamiltonian, 226 Elastic model, excess entropy calculation from, 141 of a solid solution, 140 Electric correlation, 248 Electric field gradient, 188, 189 Electron (s), 200... [Pg.405]

The CCSD model gives for static and frequency-dependent hyperpolarizabilities usually results close to the experimental values, provided that the effects of vibrational averaging and the pure vibrational contributions have been accounted for. Zero point vibrational corrections for the static and the electric field induced second harmonic generation (ESHG) hyperpolarizability of methane have recently been calculated by Bishop and Sauer using SCF and MCSCF wavefunctions [51]. [Pg.137]

In Section II, the basic equations of OCT are developed using the methods of variational calculus. Methods for solving the resulting equations are discussed in Section III. Section IV is devoted to a discussion of the Electric Nuclear Bom-Oppenhermer (ENBO) approximation [41, 42]. This approximation provides a practical way of including polarization effects in coherent control calculations of molecular dynamics. In general, such effects are important as high electric fields often occur in the laser pulses used experimentally or predicted theoretically for such processes. The limits of validity of the ENBO approximation are also discussed in this section. [Pg.45]

Moreover, for the observables depending on external electric field, its specific effect has to be investigated the electric field induces new terms in the nuclear Hamiltonian, due to the change of equilibrium geometry and the nuclear motion perturbation. Pandey and Santry (14) has brought to the fore this effect and calculated the correction which only concerns the parallel component. It is represented by the following expression ... [Pg.269]

The foundation of our approach is the analytic calculations of the perturbed wave-functions for a hydrogenic atom in the presence of a constant and uniform electric field. The resolution into parabolic coordinates is derived from the early quantum calculation of the Stark effect (29). Let us recall that for an atom, in a given Stark eigenstate, we have ... [Pg.272]


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See also in sourсe #XX -- [ Pg.332 ]




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