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Pseudopotential model for

For our pseudopotential calculations, we took the pseudopotential model for sodium that was determined many years ago in some work on lattice dynamics. The model has four parameters, two in the Harrison-type pseudopotential, and a and y in the... [Pg.546]

Zaitsevkii, A., Titov, A. Relativistic pseudopotential model for superheavy elements applications to chemistry of eka-Hg and eka-Pb. Russ. Chem. Rev. 78, 1173-1181 (2009)... [Pg.234]

The systems discussed in this chapter give some examples using different theoretical models for the interpretation of, primarily, UPS valence band data, both for pristine and doped systems as well as for the initial stages of interface formation between metals and conjugated systems. Among the various methods used in the examples are the following semiempirical Hartree-Fock methods such as the Modified Neglect of Diatomic Overlap (MNDO) [31, 32) and Austin Model 1 (AMI) [33] the non-empirical Valence Effective Hamiltonian (VEH) pseudopotential method [3, 34J and ab initio Hartree-Fock techniques. [Pg.74]

Another model which combined a model for the solvent with a jellium-type model for the metal electrons was given by Badiali et a/.83 The metal electrons were supposed to be in the potential of a jellium background, plus a repulsive pseudopotential averaged over the jellium profile. The solvent was modeled as a collection of equal-sized hard spheres, charged and dipolar. In this model, the distance of closest approach of ions and molecules to the metal surface at z = 0 is fixed in terms of the molecular and ionic radii. The effect of the metal on the solution is thus that of an infinitely smooth, infinitely high barrier, as well as charged surface. The solution species are also under the influence of the electronic tail of the metal, represented by an exponential profile. [Pg.82]

For the metal in the electrochemical interface, one requires a model for the interaction between metal and electrolyte species. Most important in such a model are the terms which are responsible for establishing the metal-electrolyte distance, so that this distance can be calculated as a function of surface charge density. The most important such term is the repulsive pseudopotential interaction of metal electrons with the cores of solvent species, which affects the distribution of these electrons and how this distribution reacts to charging, as well as the metal-electrolyte distance. Although most calculations have used parameterized simple functional forms for this term, it can now be calculated correctly ab initio. [Pg.89]

This chapter reviews models based on quantum mechanics starting from the Schrodinger equation. Hartree-Fock models are addressed first, followed by models which account for electron correlation, with focus on density functional models, configuration interaction models and Moller-Plesset models. All-electron basis sets and pseudopotentials for use with Hartree-Fock and correlated models are described. Semi-empirical models are introduced next, followed by a discussion of models for solvation. [Pg.21]

This work done is path-independent since V x R(r) = 0. For systems of certain symmetry such as closed shell atoms or open-shell atoms in the central-field approximation, the jellium and structureless-pseudopotential models of a metal surface considered here, etc., the work Wxc (r) and Wt (r) are separately path-independent since for these cases Vx xc(r) = VxZt (r) = 0. [Pg.246]

In the jellium and structureless pseudopotentials models of a metal surface, there is translational symmetry in the plane parallel to the surface and the effective potential in which the electrons move is local. Thus, the structure of the setf-consistent KS orbitals for these models is of the form... [Pg.250]

Fig. 1 Asymptotic structure coefficients as(j8), c ks,xG ) crw03), a CS), and aKS gOS) as fimction of barrier height parameter )S =VW/eF, where W is the barrier height and eF the Fermi energy. Corresponding values of the Wigner-Seitz radius rs for jellium and structureless-pseudopotential models over the metallic range of densities are also given. The relationship between rs and ff is via self-consistent calculations in the local density approximation for exchange-correlation. Fig. 1 Asymptotic structure coefficients as(j8), c ks,xG ) crw03), a CS), and aKS gOS) as fimction of barrier height parameter )S =VW/eF, where W is the barrier height and eF the Fermi energy. Corresponding values of the Wigner-Seitz radius rs for jellium and structureless-pseudopotential models over the metallic range of densities are also given. The relationship between rs and ff is via self-consistent calculations in the local density approximation for exchange-correlation.
Let us now turn to a few other informative applications of the pseudopotential model to properties (discussed extensively in Harrison, 1976a). For that purpose it will be most convenient to take the pseudopotential parameters from the LCAO values for V2 and Fj, using Eq. (18-5). We see from Table 18-1 that for V2 this is roughly equivalent to using Empirical Pseudopotential Model parameters. Let us look first at the dielectric susceptibility, which was so important in the development of the LCAO theory. For this, the most convenient form for the susceptibility is Eq. (4-5), which we rewrite in simple form,... [Pg.419]

They have additional two publications, which have the following titles FSGO study of the Gauss-type pseudopotential for the Lithium and Lithium(l-) and its isoelectronic series, ab initio molecular fragment calculations with pseudopotentials, calculation on Li2, LiH and BeH2, and Ab initio molecular fragment calculations with pseudopotentials model peptide studies . ... [Pg.294]

The use of pseudopotentials and HF/MP2/DFT models for the prediction of vibrational frequencies of metal complexes.114... [Pg.522]

Thus, we might reasonably expect that the total core potential (pseudopotential. Coulomb and exchange potentials) might well be reasonably modelled (for one... [Pg.303]

In the case of two or more valence electrons we have to make a choice which is absent from the single-electron case we must choose a model for the electronic structure. We have to decide if we shall use a single determinant for the pseudo-wavefunction (using an obvious generalisation of the term pseudo-orbital) or a more accurate model containing electron correlation. Obviously the detailed form of the pseudopotential and of the pseudo-wavefu notion will depend on this choice of model and the development will become too complex to be useful. Let us make the opposite choice look at the formal equations independent of model and see if there are some general decisions to be made which will enable us to use the theory developed so far for a single electron. [Pg.304]


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Pseudopotential

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