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Generalized density

The antisymmetrization of the trial function has a definite effect on the generalized density matrices P(x x 2.. . x x1x2. . . xv) defined by Eq. II.9 since, except for the first-order matrix, they will now all be antisymmetric in each set of the indices. For p = 2, we have in particular ... [Pg.217]

Approximations have been reviewed in the case of short deBroglie wavelengths for the nuclei to derive coupled quantal-semiclassical computational procedures, by choosing different types of many-electron wavefunctions. Time-dependent Hartree-Fock and time-dependent multiconfiguration Hartree-Fock formulations are possible, and lead to the Eik/TDHF and Eik/TDMCHF approximations, respectively. More generally, these can be considered special cases of an Eik/TDDM approach, in terms of a general density matrix for many-electron systems. [Pg.335]

For a given cation the density and viscosity of an ionic liquid are dependent on the anion in general density increases in the order BF4- < PFfi- < (CF3S02)2N and viscosity increases in the order (CF3S02)2N < BF4- < PFg- < NO3-. [Pg.156]

Polyether-based foams account for more than 90% of all flexible polyurethane foams. The properties of foams are controlled by the molecular structure of the precursors and the reaction conditions. In general, density decreases as the amount of water increases, which increases the evolution of carbon dioxide. However, the level of water that can be used is limited by the highly exothermic nature of its reaction with isocyanate, which carries with it the risk of self-ignition of the foamed product. If very low density foams are desired, additional blowing agents, such as butane, are incorporated within the mixing head. [Pg.390]

SPIN-DENSITY FUNCTIONAL THEORY General Density Functional Theory... [Pg.203]

Here it is assumed that the density n r) possesses a property of being noninteracting r-representable , which is true for most of systems [for general densities, the restriction that a variational wave function should be determi-nantal must be removed in Eq. (35)]. [Pg.65]

P. Ziesche, Pair density-functional theory — a generalized density-functional theory. Phys. Lett. A 195, 213-220 (1994). [Pg.480]

P. W. Ayers, Generalized density functional theories using the l -electron densities development of kinetic energy functionals. J. Math. Phys. 46, 062107 (2005). [Pg.480]

P. W. Ayers and M. Levy, Generalized density-functional theory conquering the A-representability problem with exact functionals for the electron pair density and the second-order reduced density matrix. J. Chem. Set 117, 507-514 (2005). [Pg.480]

Kohn, W., and Vashishta, P. (1983). General density functional theory. In Theory of the Inhomogeneous Electron Gas, edited by S. Lundqvist and N. H. March, Plenum, New York, pp. 79-147. [Pg.394]

Given the total electronic energy in Eq. (1), one can write down a general density functional n[( for a system with a fixed number of electrons N,... [Pg.157]

In spite of the negative result of Theorem 7.2.1, we can easily obtain the following general density estimate. [Pg.108]

The same condition for a phase with general density distribution p(L)— rather than our specific Schulz parent p iL)—follows from Eq. (55) as... [Pg.306]

This is still sufficiently simple that the exact spinodal condition (55)—for a system with a general density distribution p o)—can be worked out analy-... [Pg.321]

Figure 3.17 Generalized density correlation for liquids. (Bated on A. L Lydersen, R. A Greenkom, and O. A Hougen, Generalized Thermodynamic Properties of Pure Fluids, Univ. Wisconsin, Eng. Expt. Sta. Rept. 4, 1955.)... Figure 3.17 Generalized density correlation for liquids. (Bated on A. L Lydersen, R. A Greenkom, and O. A Hougen, Generalized Thermodynamic Properties of Pure Fluids, Univ. Wisconsin, Eng. Expt. Sta. Rept. 4, 1955.)...
To provide a concrete application of the tools we have developed, let us now apply the general density matrix approach to an ensemble of one-spin systems (with I = V. To set up the density matrix according to Eqs. 11.1 and 11.5, we need basis functions wave functions are simple i (1) = a and t f2) = /3, giving the four coefficients needed for Eq. 11.5 the values... [Pg.289]

Using the notation introduced, it is possible to formulate the following result which can be proved analogously to the corresponding result for the model of beads (see Refs.23"2 ). If the macromolecules is in the globular state, i.e. if the fluctuations of the generalized density n(g) are weak, the macromolecular conformational entropy is equal to... [Pg.82]

If the globular state of a macromolecule with the given generalized density distribution n( ) was somehow prepared in the absence of the interactions between the monomers, the macromolecular free energy would be equal to -TS n. The contribution of the interactions to the macromolecular free energy (in reality, it is due to the interactions that the globule is formed) is also a functional of n( ) E = E n) = F n + TS n. ... [Pg.83]

Finally, to determine two still unknown constants, n and n+, it is necessary to find the bondary conditions for the generalized density and to apply these conditions to the density bound between the core and the fringe. We note that the micromotions of the rods inside the five-dimensional core are not hindered by the flexible spacers, since the average distance between the ends of the spacers is much smaller than a. Consequently, there must be a local equilibrium with respect to two elementary acts ... [Pg.89]

The use of polarised beams in collision studies has enabled experimentalists to perform very detailed tests of theoretical models, particularly with regard to the role of electron exchange and the spin—orbit interaction in spin-dependent scattering. We will now briefly discuss the role of these interactions before using the general density matrix method to describe the more general case where more than one mechanism may contribute to the spin-dependent effects. [Pg.236]

In using Eqs. (17) and (18), the molar liquid volume of the solvent, can be estimated by resorting to generalized density correlation chart (17). The solubility parameter of the solvent can be determined based on its definition, or. [Pg.596]


See other pages where Generalized density is mentioned: [Pg.2098]    [Pg.180]    [Pg.214]    [Pg.759]    [Pg.320]    [Pg.216]    [Pg.434]    [Pg.51]    [Pg.25]    [Pg.92]    [Pg.56]    [Pg.75]    [Pg.84]    [Pg.88]    [Pg.95]    [Pg.181]    [Pg.84]    [Pg.88]    [Pg.95]    [Pg.577]    [Pg.76]    [Pg.143]   
See also in sourсe #XX -- [ Pg.270 ]




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