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Formal solution, definition

A quantum system of N particles may also be interpreted as a system of (r — N) holes, where r is the rank of the one-particle basis set. The complementary nature of these two perspectives is known as the particle-hole duality [13, 44, 45]. Even though we treated only the iV-representability for the particles in the formal solution, any p-hole RDM must also be derivable from an (r — A)-hole density matrix. While the development of the formal solution in the literature only considers the particle reduced Hamiltonian, both the particle and the hole representations for the reduced Hamiltonian are critical in the practical solution of N-representability problem for the 1-RDM [6, 7]. The hole definitions for the sets and are analogous to the definitions for particles except that the number (r — N) of holes is substituted for the number of particles. In defining the hole RDMs, we assume that the rank r of the one-particle basis set is finite, which is reasonable for practical calculations, but the case of infinite r may be considered through the limiting process as r —> oo. [Pg.32]

The concentration of extremely dilute solutions is sometimes expressed as parts per million. For example, one supplier of ultrahigh purity nitrous oxide lists the concentration of carbon monoxide as less than 0.1 ppm. A ppm concentration is analogous to a percent concentration, except you are comparing the amount of solute to a million parts of solution, rather than 100 parts. Formally, this definition has the following mathematical form. [Pg.198]

By definition, the structure factor is the sum of single-chain ( bare ) X0 and interchain H structure factors X = X0 + H. The formal solution to the OZ equations ... [Pg.111]

For the moment, since we are unencumbered by practical considerations, we can give a formal solution to the problem by simply extending the scope of the definition of our electronic coordinates Xi. Originally, each of them was a triple of numbers the values of the three spatial coordinates of each electron e.g. x, = xi,yi,Zi ). We now use s, to be the spin coordinate of particle i (deferring, for the time being the question of the spin-dependence of the wavefunction) so that our new definition for Xi is... [Pg.17]

A formal solution to this problem is available for the molecular wave functions expressed in terms of Gaussian functions (as is the general rule). Each elementary electron distribution entering in the definition of F, is described by a couple of basic functions... [Pg.444]

In simplified matrix form this is [ ][ ] = [5] or more simply AX = B. Matrix algebra is a well established branch of mathematics and will not be discussed in detail here. The reader is assumed to be famihar with basic matrix manipulations and with definitions and if not the reader is encouraged to consult any text on linear algebra. One such formal solution of a linear system of equations is expressed in terms of the inverse of the A matrix as ... [Pg.131]

In order to get at least a formal definition of the problem, we will write the exact solution to the Schrodinger equation (Eq. II. 1) in the form... [Pg.233]

A formal definition of salt hydrolysis can follow from the description outlined above. Salt hydrolysis may be defined as a reaction in which the anion or the cation of a salt reacts with the solvent water to produce acidity or alkalinity. Evidently, it is the nature of the anion or the cation constituting the salt which will determine whether the solution produced as a result of hydrolysis will be acidic or alkaline. If the matter is examined from these points of view, the following three different cases can arise. [Pg.597]

It is very often necessary to characterize the redox properties of a given system with unknown activity coefficients in a state far from standard conditions. For this purpose, formal (solution with unit concentrations of all the species appearing in the Nernst equation its value depends on the overall composition of the solution. If the solution also contains additional species that do not appear in the Nernst equation (indifferent electrolyte, buffer components, etc.), their concentrations must be precisely specified in the formal potential data. The formal potential, denoted as E0, is best characterized by an expression in parentheses, giving both the half-cell reaction and the composition of the medium, for example E0,(Zn2+ + 2e = Zn, 10-3M H2S04). [Pg.178]

Unfortunately, even the planning of green biotechnology has now evolved into a wicked problem with complex structures and no obvious causal chains. This applies also to the PA. These problems cannot be determined completely in a quantitative and scientific manner, and there are no existing solutions in the sense of definitive and objective answers alone. Wicked problems have been addressed mainly through formalized (linear) methods that are suitable only for the solution of tame problems. [Pg.294]

If an arbitrary standard state is marked with, a formal definition of a Raoultian standard state for component A of a solution is... [Pg.71]

Geminal functional theory is a very promising research area. The different varieties of antisymmetrized products are very flexible and inherently handle difficult problems, like multideterminantal molecules. The computational effort is low compared to the quality of the solutions. The perturbation theoretical approach to SSG should essentially be possible for AGP and UAGP as well. The formal definition of GFT is a flexible framework that opens up many new opportunities for exploring the nature of solutions to the Schrodinger equation. [Pg.439]

Most of the formalism to be developed in the coming sections of these lecture notes will be independent of the specific definition of the configurational basis, in which we expand the wave function. We therefore do not have to be very explicit about the exact nature of the basis states hn>. They can be either Slater determinants or spin-adapted Configuration State Functions (CSF s). For a long time it was assumed that CSF s were to be preferred for MCSCF calculations, since it gives a much shorter Cl expansion. Efficient methods like GUGA had also been developed for the solution of the Cl problem. Recent... [Pg.206]

Summing over all pairs of segments in the solution we strictly speaking rim into problems with the tf-function interaction, which could be avoided by using a potential of finite range (cf. Sect. 2.2). Furthermore the constant Uq in principle differs from the definition (5.25). We here ignore all such complications, which do not affect the essential features of the derivation. We rather argue on a purely formal level. [Pg.86]

Thus, firstly, the choice of the pure solvent as the reference state for the definition of activities of solutes in fact impairs a fair comparison of the activity of dilute solutes such as general adds to the activity of the solvent itself. Secondly, the observed first-order rate constants k or k0 for the reaction of a solute with the solvent water are usually converted to second-order rate constants by division through the concentration of water, h2o = oA iho, for a comparison with the second-order rate coefficients HA. Again, it is questionable whether the formal h2o coefficients so calculated may be compared with truly bimolecular rate constants kUA for the reactions with dilute general acids HA. It is then no surprise that the values for the rate coefficients determined for the catalytic activity of solvent-derived acids scatter rather widely, often by one or two orders of magnitude, from the regression lines of general adds.74... [Pg.348]

Equations (3) and (4) are formally identical with the earlier Kubelka s hyperbolic solutions of differential equations for forward and backward fluxes (11), although the Chandrasekhar-Klier and Kubelka s theories start from different sets of assumptions and employ different definitions of constants characterizing the scattering and absorption properties of the medium. In Kubelka s theory, the constants a, b, and Y are related to the Schuster-Kubelka-Munk (SIM) absorption K and scattering S coefficients as... [Pg.143]


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See also in sourсe #XX -- [ Pg.74 ]




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