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Energy expression general form

I Liming now to the numerator in the energy expression (Equation (2.95)), this can be broken do, n into a series of one-electron and two-electron integrals, as for the hydrogen molecule, l ach of these individual integrals has the general form ... [Pg.67]

Equation 17 can be viewed as the general form of a sum rule for an arbitrary one-electron operator O expressed in terms of the square of the transition moment of the operator and its excitation energies. [Pg.181]

This is a general form of the energy equation for a control volume useful in combustion problems. The terms can be literally expressed as... [Pg.65]

This expression is just the one which obtains for the Hartree product wave-function. The difference between this Hartree wavefunction and the Fock wavefunction of Eq. (1) is the absence of the antisymmetrizer j4 in that equation. This means that in the Hartree wavefunction each electron can be identified with a specific molecular orbital, whereas in the Fock wavefunction all electrons make use of all orbitals. The Hartree wavefunction is of course not a proper quantum mechanical wavefunction, since it is not antisymmetric in the electrons. Moreover, for the Fock wavefunction, it is in general not possible to reduce the interorbital exchange energy to zero. But the localized molecular orbitals, as defined here, represent that set of molecular orbitals for which the energy expression comes closest to the Hartree form, i.e. they come closest to being identifiable with electrons which are not exchanged among different orbitals. [Pg.43]

In that way, the thermodynamic approach with the use of conformational term of chemical potential of macromolecules permitted to obtain the expressions for osmotic pressure of semi-diluted and concentrated solutions in more general form than proposed ones in the methods of self-consistent field and scaling. It was shown, that only the osmotic pressure of semi-diluted solutions does not depend on free energy of the macromolecules conformation whereas the contribution of the last one into the osmotic pressure of semi-diluted and concentrated solutions is prelevant. [Pg.47]

For the two-particle perturbations we can easily separate the energy-components of the interacting system into different terms. The general expression of the A -th order MBPT correlation energy has the form... [Pg.237]

In the case of the flux of mass, the result is the normal component of pua. But for the flux of momentum and energy, in general the flux density is not the normal component of a vector or tensor function of (t, x), since it will depend on the extended shapes of if and Y. But in the case of short-range forces and slowly varying p, ua, E, it can be shown to have this form with sufficient approximation. Thus one is led to the familiar pressure tensor and heat flow vector Qa, both as functions of (t, x). It is to be emphasized that the general expression of these quantities involves not only expected values of products of momenta (or velocities), but the effect of intermolecular forces. [Pg.41]

The averaging of SCF energy expressions to impose symmetry and equivalence restrictions is a straightforward, if sometimes tedious, application of the Slater-Condon rules for matrix elements between determinants of orthonormal orbitals. This matter is discussed in detail elsewhere. The most general SCF programs can handle energy expressions of the form... [Pg.150]

The second approach rederives the entropy of mixing in the ideal part of the free energy in a form that depends explicitly only on the chosen moment densities. As described in Section n.B, the expression that results is intractable in general because it still contains the full complexity of the problem. However, in situations where there are only infinitesimal amounts of all... [Pg.270]

We show the equivalence of the two approaches in Section HC. There, we first demonstrate that the general form of the entropy of mixing obtained by the combinatorial method can be transformed to the standard expression — Jdon(o) In n a). Second, we show that the moment free energies arrived at by the two methods are in fact equal, with the projection method being slightly more generally applicable. [Pg.271]

For viscous energy loss, from Kozeny s equation, the pressure drop is proportional to the square of the specific surface area of solids So- For kinetic energy loss, from Burke and Plummer s relation, the pressure drop is proportional to So- So is related to the particle diameter by Eq. (5.351) for spherical particles for nonspherical particles, the dynamic diameter (see 1.2) may be used for the particle diameter. The general form of the pressure drop can be expressed as... [Pg.229]

Similarly, the activity coefficient equations (which can be derived from the excess Gibbs energy expression) have the general form ... [Pg.231]

The energy expression for a general Cl wave function can be written in the form E = Y,Dpqhpq+ E PpqrsiPdVs), (5 4)... [Pg.133]

The expression for the equilibrium constant Keq was developed from component standard free energies of formation published by Stull (6) and has the general form... [Pg.252]


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See also in sourсe #XX -- [ Pg.123 , Pg.132 , Pg.133 ]




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