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Equations integro-differential

In praotioe, solution of as an integro-differential equation oan be oarried out only for atoms [34] and... [Pg.2169]

The HF equations F ( )i = 8i (jii comprise a set of integro-differential equations their differential nature arises from the kinetic energy operator in h, and the coulomb and exchange operators provide their integral nature. The solutions of these equations must be... [Pg.463]

From (5.56) one can obtain an integro-differential equation for operator What we need is the mean particle position, <(Tz>, and in order to find it two approximations are made. First, in taking the bath averages we assume free bath dynamics. Second, we decouple the bath and pseudospin averages, guided by perturbation theory. The result is a Langevin-like equation for the expectation <(T2> [Dekker 1987a Meyer and Ernst 1987 Waxman 1985],... [Pg.85]

The population balance is a partial integro-differential equation that is normally solved by numerical methods, except for special simplified cases. Numerical solution of the population balance for the general case is not, therefore, entirely straightforward. Ramkrishna (1985) provides a comprehensive review. [Pg.56]

Differentiation of Eq. (8) with respect to the position of a molecule gives a hierarchy of integro-differential equations, each of which relates a distribution function to the next higher order distribution function. Specifically,... [Pg.139]

In fact, the HF procedure leads to a complicated set of integro-differential equations that can only be solved for a one-centre problem. If your interest lies in atomic applications, you should read the classic books mentioned above. What we normally do for molecules is to use the LCAO procedure each HF orbital is expressed as a linear combination of n atomic orbitals X . Xn... [Pg.113]

I have dealt at length with the Hartree and the Hartree-Foek models. The father of this field, Sir Wilham Hartree, was eoneemed with the atomie problem where it is routinely possible to integrate numerieally the HF integro-differential equations in order to produee (numerieal) wavefunetions that eorrespond to the Hartree-Foek limit. For moleeular applieations the LCAO variant of HF theory assumes a dominant role beeause of the redueed symmetry of the problem. [Pg.209]

The last term in Eq. 11.47 gives apparently the "average one-electron potential we were asking for in Eq. 11.40. The Hartree-Fock equations (Eq. 11.46) are mathematically complicated nonlinear integro-differential equations which are solved by Hartree s iterative self-consistent field (SCF) procedure. [Pg.226]

The resulting model of raulticonponent enulsion pjolymerization systems is consituted by the Pffil 17, an integro-differential equation, a set of ordinary differential equations (equation 18 and 25 and the equations for pjoiymer conposltlon) and the system of the remaining non linear algebraic equations. As expected the conputatlonal effor t is concentrated on the solution of the PBE therefore, let us examine this aspect with some detail. [Pg.386]

J. M. Appeil et ai., Partial Integral Operators and Integro-Differential Equations (2000)... [Pg.771]

Mathematical physics deals with a variety of mathematical models arising in physics. Equations of mathematical physics are mainly partial differential equations, integral, and integro-differential equations. Usually these equations reflect the conservation laws of the basic physical quantities (energy, angular momentum, mass, etc.) and, as a rule, turn out to be nonlinear. [Pg.774]

Since this integro-differential equation depends not only on p2 but also, through the two integral terms, on and p, it is indeterminate [43]. [Pg.67]

The benefit is now that the HF equations are turned from complicated integro-differential equations into pseudo-eigenvalue equations for the unknown expansion coefficients c. [Pg.141]

Hence, through the LCAO expansion we have translated the non-linear optimization problem, which required a set of difficult to tackle coupled integro-differential equations, into a linear one, which can be expressed in the language of standard linear algebra and can easily be coded into efficient computer programs. [Pg.111]

For a CSTR, (1.18) is numerically unstable for small hem (Fox 1989). For numerical work, it should thus be replaced by an equivalent integro-differential equation (Fox 1991). [Pg.32]

Although this definition can be employed to find the mean concentrations, it is numerically unstable for small values of fm. In this case, an equivalent integro-differential equation is preferable (Fox 1989 Fox and Villermaux 1990b). [Pg.213]

The results discussed so far are a consequence of the determinantal form of the molecular orbital wavefunction jj. They are valid for an arbitrary choice of molecular orbitals uk. Of particular interest are, however, those space orbitals which render p optimal, i.e. that molecular orbital (MO) approximation which is closest to the true wavefunction. The optimal molecular orbitals are those which minimize 3C iii), and Fock 6) has shown that they are the solutions of the integro-differential equations... [Pg.37]

Rigorous treatment of the self-action problem needs the transformation of Eq.(2.1), (2.5) into a system of integro-differential equations. However, if just some orders of group velocity dispersion and nonlinearity are taken into account, an approximate approach can be used based on differential equations solution. When dealing with the ID-i-T problem of optical pulse propagation in a dielectric waveguide, one comes to the wave equation with up to the third order GVD terms taken into account ... [Pg.152]

The practical implementation of this method leads to an integro-differential equation which has been solved for atoms [23] leading to the most consistent relativistic Thomas-Fermi estimations known up to now. The energy values for some atoms are displayed in Table 2 compared to Dirac-Fock ones. [Pg.200]

The result of the variational method leads to the Hartree-Fock non-linear integro-differential equations for a one electron wave function... [Pg.31]

By substitution of this expansion in Eq. (9.52), one obtains a system of coupled integro-differential equations (IDE) for the bj t) and bj t) coefficients, corresponding to states in the and Q2 subspaces, respectively, given by... [Pg.376]

These are the glorious Hartree-Fock equations derived in general in the spin orbital basis. But wait - there s a problem. These are coupled integro-differential equations, and while they are not strictly unsolvable, they re a pain. It would be nice to at least uncouple them, so let s do that. [Pg.18]

Now we introduce a basis set expansion to bring the HF integro-differential equations to soluable algebraic equations. Letting =... [Pg.20]


See other pages where Equations integro-differential is mentioned: [Pg.2049]    [Pg.72]    [Pg.464]    [Pg.537]    [Pg.477]    [Pg.64]    [Pg.200]    [Pg.297]    [Pg.132]    [Pg.133]    [Pg.110]    [Pg.317]    [Pg.38]    [Pg.345]    [Pg.354]    [Pg.19]    [Pg.3]    [Pg.3]    [Pg.16]    [Pg.107]    [Pg.38]    [Pg.125]    [Pg.340]    [Pg.19]   
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See also in sourсe #XX -- [ Pg.214 ]

See also in sourсe #XX -- [ Pg.255 ]

See also in sourсe #XX -- [ Pg.255 ]




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