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Self-consistent solutions

Viscoelastic contact problems have drawn the attention of researchers for some time [2,3,104,105]. The mathematical peculiarity of these problems is their time-dependent boundaries. This has limited the ability to quantify the boundary value contact problems by the tools used in elasticity. The normal displacement (u) and pressure (p) fields in the contact region for non-adhesive contact of viscoelastic materials are obtained by a self-consistent solution to the governing singular integral equation given by [106] ... [Pg.122]

The LSDA approach requires simultaneous self-consistent solutions of the Schrbdinger and Poisson equations. This was accomplished using the Layer Korringa-Kohn-Rostoker technique which has many useful features for calculations of properties of layered systems. It is, for example, one of only a few electronic structure techniques that can treat non-periodic infinite systems. It also has the virtue that the computational time required for a calculation scales linearly with the number of different layers, not as the third power as most other techniques. [Pg.274]

In this framework, we have developed an analytical model based on a self-consistent solution of the Poisson equation using an adiabatic approximation for laser generated fast electrons [75], This model, briefly outlined in the following, allows the determination of the optimal target thickness to optimize the maximum proton (and ion) energies, as well as the particle number as a function of given UHC laser pulse parameters. [Pg.203]

Thus, let us consider first the KS approach [34] in which the spin-orbitals ifr,(r) are self-consistent solutions of the equations... [Pg.17]

General expression for the fluctuation contribution to the specific heat is given by the first line (15) and can be resolved with the help of the self-consistent solution of (11), (19) (or (20), (21), (22) in the limiting cases). Assuming for rough estimates that fluctuations can be described pcrturbativcly and putting m2 — r/ vip u, from the second line of (15) we find for T <. [Pg.285]

That is, the classical DoF propagate according to a mean-field potential, the value of which is weighted by the instantaneous populations of the different quantum states. A MFT calculation thus consists of the self-consistent solution of the time-dependent Schrodinger equation (28) for the quantum DoF and Newton s equation (32) for the classical DoF. To represent the initial state (15) of the molecular system, the electronic DoF dk Q) as well as the nuclear DoF xj Q) and Pj 0) are sampled from a quasi-classical phase-space distribution [23, 24, 26]. [Pg.269]

The simplesf mefhod of solution of fhe Kirchhoff equations that correspond to the random network of conducfance elemenfs in three dimensions is in the single-bond effective medium approximation (SB-EMA), wherein a single effective bond between two pores is considered in an effective medium of surrounding bonds. The conductivify (7b, of fhe effective bond is obtained from the self-consistent solution of fhe equation ... [Pg.392]

The challenge for modeling the water balance in CCL is to link the composite, porous morphology properly with liquid water accumulation, transport phenomena, electrochemical kinetics, and performance. At the materials level, this task requires relations between composihon, porous structure, liquid water accumulation, and effective properhes. Relevant properties include proton conductivity, gas diffusivihes, liquid permeability, electrochemical source term, and vaporizahon source term. Discussions of functional relationships between effective properties and structure can be found in fhe liferafure. Because fhe liquid wafer saturation, 5,(2)/ is a spatially varying function at/o > 0, these effective properties also vary spatially in an operating cell, warranting a self-consistent solution for effective properties and performance. [Pg.415]

Figure 3. Values of the energy obtained for each iteration in the self-consistent solution of the 2-CSE for different values of in the ground state of the BeH2 molecule. Figure 3. Values of the energy obtained for each iteration in the self-consistent solution of the 2-CSE for different values of in the ground state of the BeH2 molecule.
As can be seen, the 2-CSE depends not only on the 2-RDM but also on the 3- and 4-RDMs. This fact lies at the root of the indeterminacy of this equation [63, 107]. As already mentioned, in the method proposed by Colmenero and Valdemoro [46 8] and in those further proposed by Nakatsuji and Yasuda [49, 51] and by Mazziotti [52, 111], a set of algorithms for approximating the higher-order ROMs in terms of the lower-order ones [46, 47, 108] allows this equation to be solved iteratively until converging to a self-consistent solution. In the approach considered in this work, the spin-adapted 2-CSE has been used. This equation is obtained by coupling the 2-CSE with the second-order contracted spin equation [50]. [Pg.246]

Initially, the main features of the iterative self-consistent solution of the 2-CSE were the following [48] ... [Pg.246]

We also need to think about how to stop our iterative calculations. It is not necessarily convenient to directly compare two solutions for the electron density and determine how similar they are, even though this is the most direct test for whether we have found a self-consistent solution. A method that is easier to interpret is to calculate the energy corresponding to the electron density after each iteration. This is, after all, the quantity we are ultimately interested in finding. If our iterations are converging, then the difference in energy between consecutive iterates will approach zero. This suggests that the iterations can... [Pg.74]

Before moving on from this section, it would be a good idea to understand within the DFT package that is available to you (i) what algorithms are used for solving the self-consistent Kohn-Sham problem and (ii) how you can verify from the output of a calculation that a self-consistent solution was reached. [Pg.75]

This is plotted in the right-hand panel of Fig. 3.8 as a function of I/2 h. Remembering that h(R) - 0 as R - oo, we see that it shows the same square root distance-dependence as that displayed by the numerical self-consistent solution of the local spin density functional Schrddinger equation in Fig. 3.6. Thus, as the hydrogen molecule is pulled apart, it moves from the singlet state S = 0 at equilibrium to the isolated free atoms in doublet states with S = 2-... [Pg.64]

Recently, Ya.B. has been working on a complete cosmological theory which would incorporate the creation of the Universe (1982) [45 ]. Let us mention finally that it was Ya.B. who recently gave a profound formulation of the question of the cosmological constant, i.e., the energy density in Minkovsky space (see Section 9). More precisely, the question is formulated thus is the Minkovsky space a self-consistent solution of the equations for all possible fields and the equations of general relativity ... [Pg.43]

QR Method. The first relativistic method is the so-called quasi-relativistic (QR) method. It has been developed by Snijders, Ziegler and co-workers (13). In this approach, a Pauli Hamiltonian is included into the self-consistent solution of the Kohn-Sham equations of DFT. The Pauli operator is in a DFT framework given by... [Pg.103]


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See also in sourсe #XX -- [ Pg.14 , Pg.23 ]




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