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Theory, formulation

Correlation can be added as a perturbation from the Hartree-Fock wave function. This is called Moller-Plesset perturbation theory. In mapping the HF wave function onto a perturbation theory formulation, HF becomes a hrst-order perturbation. Thus, a minimal amount of correlation is added by using the second-order MP2 method. Third-order (MP3) and fourth-order (MP4) calculations are also common. The accuracy of an MP4 calculation is roughly equivalent to the accuracy of a CISD calculation. MP5 and higher calculations are seldom done due to the high computational cost (A time complexity or worse). [Pg.22]

Let us compare these results with the predictions of the theory formulated by Lampe etal. (24) in terms of a steady-state concentration of collision complexes. This is a classical macroscopic treatment insofar as it makes no assumptions about the collision dynamics, but its postulate of collision complexes implies that v8 = vp/2 for the system treated above. Thus, its predictions might be expected to coincide with those of the collision-complex model. Figure 3 shows that this is not so the points calculated from the steady-state theory (Ref. 25, Equation 10) coincide exactly with the curve for which v8 = vv. The reason for this is that the steady-state treatment assumes a constant time available for reaction irrespective oC the number of reactions occurring in any one reaction... [Pg.148]

Scattering theory formulates the observables of collisions and bound-free experiments in terms of the partial wave phase shifts, which distinguish the... [Pg.151]

Note that the choice of non-orthogonal versus orthogonal basis functions has no consequence for the numerical variational solutions (cf. Coulson s treatment of He2, note 76), but it undermines the possibility of physical interpretation in perturbative terms. While a proper Rayleigh-Schrodinger perturbative treatment of the He- He interaction can be envisioned, it would not simply truncate at second order as assumed in the PMO analysis of Fig. 3.58. Note also that alternative perturbation-theory formulations that make no reference to an... [Pg.357]

Construct validation follows a three-stage process. The first stage, theory formulation, involves specifying relationships among constructs and their relation to external variables (e.g., etiological factors). Disorder x is created by process y. For example, a theory about the construct panic disorder could specify that it is caused by the catastrophic misinterpretation of benign bodily cues (Clark, 1986) or by a faulty suffocation monitor (Klein, 1993). Internal... [Pg.6]

Consequently, from the density the Hamiltonian can be readily obtained, and then every property of the system can be determined by solving the Schrodinger equation to obtain the wave function. One has to emphasize, however, that this argument holds only for Coulomb systems. By contrast, the density functional theory formulated by Hohenberg and Kohn is valid for any external potential. Kato s theorem is valid not only for the ground state but also for the excited states. Consequently, if the density n, of the f-th excited state is known, the Hamiltonian H is also known in principle and its eigenvalue problem ... [Pg.123]

There is another important law that follows from the classical theory of capillarity. This law was formulated by J. Thomson [16], and was based on a Clausius-Clapeyron equation and Gibbs theory, formulating the dependence of the melting point of solids on their size. The first known analytical equation by Rie [17], and Batchelor and Foster [18] (cited according to Refs. [19,20]) is... [Pg.265]

By contrast the alternative approach of perturbation theory formulates an approximation for A in terms of the original single well wavefunctions as... [Pg.69]

In the remaining part of the present article, we shall consider further consequences of the main results of the theory formulated in the preceding paragraphs. We shall begin with the mechanism of the influence of chemisorption on certain properties of the semiconductor. [Pg.230]

I agree with looking at these matters in different ways. As I understand it, you do not object to the transition state theory formulation. The one word of caution I would like to interject, though, is this you spoke of the caged species before it had really reached the activated complex configuration, and you spoke of this concept s being particularly valuable. [Pg.255]

How is the light scattering theory formulated for large, absorbing particles What is meant by absorbing particles ... [Pg.243]

The measurement of relaxation times 7j and T2 and the subsequent application of the theory formulated by Bloembergen et al. (236), and extended by Kubo and Tomita (272) and Torrey (288), leads to the determination of motional and thermodynamic parameters such as mean times between molecular jumps, diffusion coefficients, and activation enthalpies for translation. For example, Resing and Thompson (289, 290) used this... [Pg.305]

The resonance theory," to be discussed in detail in Chapters 6 and 21, was characterized in 1949 as a physically and ideologically inadmissable theory formulated by decadent bourgeois scientists. See L. R. Graham, Science and Philosophy in the Soviet Union, Vintage Books, New York, 1974, Chapter VIII, for an interesting account of this controversy. [Pg.11]

This review has surveyed the present status of theoretical and experimental studies on the adsorption of macromolecules, with particular reference to the determination of conformations of adsorbed macromolecules. No definitive experimental method is as yet available for this determination. At present, the conformation of adsorbed macromolecules can only be inferred from a comparison of experimental data of such properties as the adsorbed amount T, the fraction p of adsorbed trains and the thickness of the adsorbed layer with the existing theories formulated on various conformational models as depicted in Fig. X. [Pg.61]

Translating the preceding equations into a group theory formulation, in order to relate the three major soliton equations to group theory, it is necessary to... [Pg.708]

My own criticism on the theories proposed for superplasticity can be summarized in one word, electrons , or more accurately the lack of electronic consideration. This is similar to the theoretical consideration brought forward in the study of LME (liquid metal embrittlement) described in the previous chapter - no electronic consideration. As shown in Table 2, all superplastic alloys of binary system are found either at eutectic or eutectoid compositions. This is illustrated in Fig. 14 in which a few binary phase diagram involving superplastic alloys are shown. However, the people who made efforts in the formulation of theories did not consider this well-known fact important enough to incorporate into their theory formulation [24], In fact, this observation is so consistent one should ask the question of the special attributes associated with eutectic or eutectoid composition. Or the fact that the intermetallic compounds with superelastic property are all of the peritectic type. It must be emphasized that to this date there is no report of finding superplasticity in congruently-melting compounds. [Pg.174]

Let us first analyze the effect of the bias field on the magnetic SR in the framework of the linear response theory formulated for SR [96,97,99]. The main idea of the linear response treatment is a direct use of the fluctuation-dissipation theorem, which expresses the thermal (fluctuational) power spectrum Qn(a>) of the magnetic moment of the system, namely, magnetic noise, through the imaginary component of its linear dynamic susceptibility ImX = to a weak probing ac field of an arbitrary frequency co as... [Pg.528]

Finally, in this section, the possible role of counterion displacements in relaxation of globular proteins should be mentioned. These can result in fluctuating dipole moments in addition to permanent moments p. along principal molecular axes. If their relaxations are independent and separately exponential with rate constants k and k, response theory formulation gives the complex permittivity in the form... [Pg.69]

Nowadays, the basic framework of our understanding of elementary processes is the transition state or activated complex theory. Formulations of this theory may be found in refs. 1—13. Recent achievements have been the Rice—Ramsperger—Kassel—Marcus (RRKM) theory of unimol-ecular reactions (see, for example, ref. 14 and Chap. 4 of this volume) and the so-called thermochemical kinetics developed by Benson and co-workers [15] for estimating thermodynamic and kinetic parameters of gas phase reactions. Computers are used in the theory of elementary processes for quantum mechanical and statistical mechanical computations. However, this theme will not be discussed further here. [Pg.249]

An incipient theory proposed by Train [27] related lamination to radial elastic recovery of the compacted material during ejection. A once-accepted theory formulated that capping and lamination are the result of air entrapped in the tablet under pressure which tries to escape during ejection [28], This theory is no longer widely accepted. Disagreement arises from the fact that some formulations cap or laminate even at low press speeds. Today, it is believed that the entrapped air may be related to capping but does not affect lamination. [Pg.1157]

The experimental results are compared with theoretical calculations using strictly empirical as well as Sato potential energy surfaces and a transition state theory formulation of the rate coefficient ratio. No one set of potential parameters could be found to fit all the data but it is not possible to attribute the deviations either to experimental error or the theory. [Pg.223]

The relationship between excitation transport and fluorescence depolarization in two and three dimensional disordered systems has been discussed by Anfinrud and Struve . In the usual discussion of excitation transport by dipole-interaction it is conventional to assume that excitation is completely depolarized after a single hop. This supposition has been critically examined and a theory formulated suitable for application to Langmuir Blodgett films and absorbed species. [Pg.23]

Penn, L.E. Gel dosage forms theory, formulation, and processing. In Topical Drug Delivery Eormulations Osborne, D.W., Amann, A.H., Eds. Marcel Dekker, Inc. New York, 1990 381-338. [Pg.1890]

Some PCM calculations (e.g. Bachs et al., 1994) exploit a numerical correlation between Gcav (and Gdis) and the volume and surface of the solute, drawn from Floris and Tomasi s calculations (1989). The Scaled Particle Theory formulation for a spherical cavity is based on the volume. Pierotti s expansion leads to a formula where both volume and surface terms are... [Pg.41]


See other pages where Theory, formulation is mentioned: [Pg.68]    [Pg.239]    [Pg.316]    [Pg.352]    [Pg.118]    [Pg.6]    [Pg.7]    [Pg.331]    [Pg.343]    [Pg.16]    [Pg.43]    [Pg.115]    [Pg.466]    [Pg.751]    [Pg.143]    [Pg.126]    [Pg.39]    [Pg.174]    [Pg.269]    [Pg.68]    [Pg.479]   
See also in sourсe #XX -- [ Pg.3 , Pg.12 ]




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Alternative Formulation from Estimation Theory

Brillouin-Wigner coupled-cluster theory, single-root formulation

Density functional theory formulation

Effective potential theory basic formulations

Exact Formulation of the Adiabatic Theory

Excited states, perturbation theory formulation

Formulation of the Kinetic Theory

Formulation of the Molecular Theory

Formulation of the theory

General Matrix Formulation of Fluctuation Theory

Generalized perturbation theory formulations

Graph theory formulation

Integral transport theory, formulations

Perturbation theory formulation

Perturbation theory single-root formulation

Reactivity integral transport theory formulations

Response functions perturbation theory formulation

Single-root formulation of multi-reference Brillouin-Wigner perturbation theory

Single-root formulation of the multi-reference Brillouin-Wigner coupled-cluster theory

Sufficient Theories for State-Space Formulation

Sufficient theory state-space formulation

The Bohr Model Was an Early Attempt to Formulate a Quantum Theory of Matter

Theory Formulation of Reaction Rates

Thermodynamic formulation of transition state theory

Transition state theory thermodynamic formulation

Valence bond theory Heitler-London formulation

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