Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Sturm-Liouville equation

First we consider the Sturm-Liouville equation over the interval a z /8 ... [Pg.23]

At times t < f0 w [where f0 ° is an infinitesimal amount less than f0 ], the density is zero. Only after the pair is formed can there be any probability of its existence [499]. This is cause and effect, but strictly only applicable at a macroscopic level. On a microscopic scale, time reversal symmetry would allow us to investigate the behaviour of the pair at time and so it reflects the inappropriateness of the diffusion equation to truly microscopic phenomena. The irreversible nature of diffusion on a macroscopic scale results from the increase of entropy, and should be related to microscopic events described by the Sturm—Liouville equation (for instance) and appropriately averaged. [Pg.370]

It is convenient to use spherical polar coordinates (r, 0, ) for any spherically symmetric potential function v(r). The surface spherical harmonics V,1" satisfy Sturm-Liouville equations in the angular coordinates and are eigenfunctions of the orbital angular momentum operator such that... [Pg.39]

The effective eigenvalue may be defined in the context of the Sturm-Liouville equation as [78]... [Pg.370]

Fuoss and Kirkwood32 have obtained equations identical with Eqs. 31 and 32 without introducing, explicitly, the exponential decay function. Like Debye they reasoned as if the problem were mainly one of diffusion by Brownian motion under the influence of an external force. Treating this problem as a Sturm-Liouville equation, they developed /lt into a complete set of orthogonal functions yx. A relaxation time rx is associated with each of these functions. [Pg.87]

The physical description of the functional derivative Vee (r) requires knowledge of the wavefunction 4 for the determination of the electron-interaction component W e(r) = Wnlr) -i- W (r), and knowledge of both the wavefunction P and the Kohn-Sham orbitals < i(x) for the correlation-kinetic-energy component W, (r). The corresponding Kohn-Sham wavefunction is then a single Slater determinant. It has, however, also been proposed [42,52,53] that the wavefunction V be determined by solution of the Sturm-Liouville equation... [Pg.37]

The weighting function for this particular orthogonality condition defined with reference to the Sturm-Liouville equation is... [Pg.287]

This appears to be a formidable task. To accomplish it, we shall need some new tools. Under certain conditions, it may be possible to compute C without a trial-and-error basis. To do this, we shall need to study a class of ODE with homogeneous boundary conditions called the Sturm-Liouville equation. We shall return to the coated-wall reactor after we gamer knowledge of the properties of orthogonal functions. [Pg.425]

It is clear that Eq. 10.225 is a Sturm-Liouville equation with... [Pg.432]

It is clear that the heat balance produces an inhomogeneous equation, owing to the (assumed) constant heat source term Q. This means of course that a separation of variables approach will not lead to a Sturm-Liouville equation. However, the following expedient will produce a result that is homogeneous let temperature be decomposed into two parts a steady state (the future steady state) and a deviation from steady state... [Pg.435]

Because they depend on the Sturm-Liouville equation, the separation of variables method and the integral transform yield exactly the same solution, as you would expect. But the advantage of the integral transform is the simplicity of handling coupled PDEs, for which other methods are unwieldy. Moreover, in applying the finite integral transform, the boundary conditions need not be homogeneous (See Section 11.2.3). [Pg.488]

Transforms in Finite Domain Sturm-Liouville Transforms 493 Sturm-Liouville equation) is obviously. [Pg.493]

Ag)l2 Cf is the normalized intensity of the lines J and 7 and p is the probability of hopping per time unit. In Brown s model (see Section D.3.2), the relaxation mode given by the smallest nonvanishing eigenvalue, Aj, of the Sturm-Liouville equation is the only significant mode. ... [Pg.416]

This results from the fact that the separation leads to a Sturm-Liouville equation for each coordinate, for which the theorem mentioned above is valid. Also in the cases where the boundary conditions do not require 4 to vanish, but only require that 4 remain finite, there are no significant changes. [Pg.224]

Coulomb Sturmians (CSs) are an exponential-type complete set of basis functions which satisfy a Sturm-Liouville equation [2]. The main objective of the present work is to derive an ADT for the Slater-type orbitals (STOs), which are the fundamental ETO, and thereby for the CSs, which are a linear combination of STOs. The expression for the two-center overlap integral is then worked out for the CSs as an illustration and numerical results and conclusions are presented. [Pg.72]

Coulomb Sturmians have the advantage of constituting a complete set without continuum states because they are eigenfunctions of a Sturm-Liouville equation involving the nuclear attraction potential i.e., the differential equation below. [Pg.85]


See other pages where Sturm-Liouville equation is mentioned: [Pg.603]    [Pg.274]    [Pg.370]    [Pg.424]    [Pg.287]    [Pg.426]    [Pg.426]    [Pg.495]    [Pg.516]    [Pg.663]    [Pg.664]    [Pg.313]    [Pg.420]    [Pg.86]   
See also in sourсe #XX -- [ Pg.426 , Pg.495 ]




SEARCH



Liouville equation

Sturm

© 2024 chempedia.info