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Theory Treatment

The derivation of the exact collision theory rate expression (51 111) presumes that the transition probabilities 1 nni( x  [Pg.145]

III) are known from accurate quantum-mechanical calculations which we discussed in Sec.4.II This expression may be used, of course, for approximate calculations, too, if exact data for are not avai- [Pg.145]

The classical and semiclassical approximations to the rate equation (51 111) are of particular interest insofar as the transition probabilities can be relatively easily computed, for instance, by classical trajectory methods (See Sec.3 II.). In this case, instead of (51 111), we write [Pg.145]

In this case the classical partition function of reactants be used,instead of However, in a semiclassical approximation, we [Pg.146]

In purely classical calculations the factor m into account through non-separability of the reaction co- [Pg.146]


This is the final result of the first-order time-dependent perturbation theory treatment of light-indueed transitions between states i and f. [Pg.381]

The optimised interlayer distance of a concentric bilayered CNT by density-functional theory treatment was calculated to be 3.39 A [23] compared with the experimental value of 3.4 A [24]. Modification of the electronic structure (especially metallic state) due to the inner tube has been examined for two kinds of models of concentric bilayered CNT, (5, 5)-(10, 10) and (9, 0)-(18, 0), in the framework of the Huckel-type treatment [25]. The stacked layer patterns considered are illustrated in Fig. 8. It has been predicted that metallic property would not change within this stacking mode due to symmetry reason, which is almost similar to the case in the interlayer interaction of two graphene sheets [26]. Moreover, in the three-dimensional graphite, the interlayer distance of which is 3.35 A [27], there is only a slight overlapping (0.03-0.04 eV) of the HO and the LU bands at the Fermi level of a sheet of graphite plane [28,29],... [Pg.47]

In a perturbation theory treatment of the total (not just electrostatic) interaction between the molecule and the point charge, QV(r) is the first-order term in the expression for the total interaction energy (which would include polarization and other effects). [Pg.53]

Second-order Perturbation Theory Treatment of Spin Hamiltonian with Non-coincident... [Pg.133]

As it happens, the only components of the -matrix we will need to know (for the perturbation theory treatment) are S33, S32 and S33 ... [Pg.136]

Putting together all the bits and pieces of the above perturbation theory treatment of quadrupole coupling effects, we arrive at the following equations ... [Pg.148]

The various response tensors are identified as terms in these series and are calculated using numerical derivatives of the energy. This method is easily implemented at any level of theory. Analytic derivative methods have been implemented using self-consistent-field (SCF) methods for a, ft and y, using multiconfiguration SCF (MCSCF) methods for ft and using second-order perturbation theory (MP2) for y". The response properties can also be determined in terms of sum-over-states formulation, which is derived from a perturbation theory treatment of the field operator — [iE, which in the static limit is equivalent to the results obtained by SCF finite field or analytic derivative methods. [Pg.16]

Another similar approach applies an explicit density-functional theory treatment to the solute molecules, while representing the contribution of the solvent molecules as an effective potential [105]. [Pg.337]

They also discussed the reaction in terms of model activated complexes for a transition state theory treatment. Jones48 in 1951 determined the relative rates of reactions (21) and (25). [Pg.153]

The remaining two are the unchanged 2py and orbitals. There are six electrons to be placed in these orbitals, and for the linear structure, the lowest two, A and B, will be filled, and the Ipy, and 2p will have a single electron each. Hund s rule suggests that the triplet state with parallel spins will be lower in energy than the singlet state (Fig. 7.1). For an related, alternative valence-shell electron-pair repulsion (VESPR) theory treatment see Chapter 11 by Platz in this volume. [Pg.276]

In transmission microscopy of specimens with properties not too different from those of water, Rayleigh waves may safely be disregarded. But in reflection microscopy of specimens of higher stiffness, Rayleigh waves generally play a dominant role. This is recognized explicitly in the ray theory treatment. [Pg.111]

Slater s band-theory treatment of Mott-Hubbard insulators... [Pg.136]

P. Borowski, J. Jaroniec, T. Janowski, and K. Wolinski. Quantum cluster equilibrium theory treatment of hydrogen-bonded liquids water, methanol and ethanol. Mol. Phys. 101, 1413-21 (2003). [This paper suggests the need for more accurate treatment of free cluster rotations that become hindered librations at normal liquid densities, thus reducing the populations of larger clusters.]... [Pg.462]

Because of the transparency of interpretation, it is convenient to start with the original Tannor-Rice perturbation theory treatment of control of molecular dynamics. We consider a molecule that can undergo fragmentation to produce two products ... [Pg.227]

Theory treatment of the hydrogen molecule. Their method has come to be known as the... [Pg.618]

Contrary to the previously described supermolecular approach, perturbation theory treatment allows for the partition of the interaction energy into physically interpretable components. The most frequently used method for this purpose is symmetry-adapted perturbation theory (SAPT) [13]. More recently, great effort has also been invested in the development of DFT-SAPT [14-16], In the present contribution, we use the variational-perturbational scheme [17-20], In this approach, the intermolecular interaction energy components are determined based on the wave functions of the subsystems evaluated in the dimer-centered basis set. Thus, both interaction energy and its components are BSSE-free. More details about this scheme can be found elsewhere [21-23]. The total intermolecular interaction energy at the MP2 level of theory can be expressed as follows ... [Pg.389]

The usefulness of electrical response measurements of solutions is not limited to effects linear in applied field. Transient birefringence induced by polarizing electric fields (the transient or dynamic Kerr effect) has given valuable information about biopolymers in solution the effect must by symmetry be an even function of E(t), beginning with terms in E (t). In both cases, a response theory treatment of transient behavior meets with difficulties not encountered in linear problems, but recent progress in deriving correlation function expressions for such effects is described in III. [Pg.64]

This electro-optical effect, commonly observed as transient changes in optical birefringence of a solution following application, removal, or reversal of a biasing electric field E(t), has been used extensively as a probe of dynamics of blopolymer solutions, notably by O Konski, and is a valuable tool because it gives information different in form, but related to, results from conventional dielectric relaxation measurements. The state of the subject to 1975 has been comprehensively presented in two review volumes edited by O Konski (25). The discussion here is confined to an outline of a response theory treatment, to be published in more detail elsewhere, of the quadratic effect. The results are more general than earlier ones obtained from rotational diffusion models and should be a useful basis for further theoretical and experimental developments. [Pg.71]

We shall consider in detail the predictions of the hard-sphere model for the viscosity, thermal conductivity, and diffusion of gases indeed, the kinetic theory treatment of these three transport properties is very similar. But first let us consider the simpler problem of molecular effusion. [Pg.120]

At variance with electrostatic theories, treatments based on scaled particle theory... [Pg.11]

More recently, Kauh et al. (K3) calculated the local heat- and mass-transfer coefficients for a flat plate by extending the turbulent analogy theory treatment of Kestin and Persen (K4) and Gardner and Kestin (Gl), and by employing the Spalding (S13) equation for the law of the wall. [Pg.251]


See other pages where Theory Treatment is mentioned: [Pg.11]    [Pg.13]    [Pg.257]    [Pg.26]    [Pg.138]    [Pg.146]    [Pg.10]    [Pg.301]    [Pg.83]    [Pg.103]    [Pg.668]    [Pg.606]    [Pg.192]    [Pg.339]    [Pg.212]    [Pg.454]    [Pg.81]    [Pg.2]    [Pg.257]    [Pg.32]    [Pg.289]    [Pg.2441]   


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Coupled-cluster theory approximate triples treatment

Density functional theory approximate treatment

Density matrix treatment theory

Many-electron theory, relativistic treatments

Perturbation Theory Treatment of Hyperfine Term

Perturbation Theory Treatment of Quadrupole Term

Quantum mechanical treatment of radiation theory

Regular solution theory, treatment

Slaters band-theory treatment of Mott-Hubbard insulators

Statistical Theory Treatment

Transition State Theory in the Treatment of Hydrogen Transfer Reactions

Transition state theory kinetic treatment

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