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Various Contributions to

In the following we shall be using a separation of the pair potential function, either (8.7.11) or (8.7.12), by writing [Pg.594]

The three terms in (8.7.23) correspond to the following three hypothetical processes Suppose we switch off the soft and all FG interactions. We are left with the two hard particles corresponding to the solutes P and L. We bring these two hard particles to form the hard complex PL. The corresponding contribution to 5G is 8G. The second term [Pg.594]

The E (for external) group consists of all FG the solvation properties of which are unchanged in the process (8.7.1). Intuitively, any FG that when switched off in the initial state (separated P and L) and switched off in the final state (the complex PL) does not affect SG will belong to the E group. Clearly, these FGs are likely to be external to the scene where changes do occur in the association process (see Fig. 8.7). [Pg.595]

The formal definition of a FG in the E group in terms of the solvation Gibbs energy is [Pg.595]

FIGURE 8.7. External functional groups in the folding and association processes. The solvation spheres around these groups are unchanged in the processes. [Pg.595]


It is usefiil to classify various contributions to intennolecular forces on the basis of the physical phenomena that give rise to them. The first level of classification is into long-range forces that vary as inverse powers of the distance r , and short-range forces that decrease exponentially with distance as m exp(-ar). [Pg.185]

The main cost of this enlianced time resolution compared to fluorescence upconversion, however, is the aforementioned problem of time ordering of the photons that arrive from the pump and probe pulses. Wlien the probe pulse either precedes or trails the arrival of the pump pulse by a time interval that is significantly longer than the pulse duration, the action of the probe and pump pulses on the populations resident in the various resonant states is nnambiguous. When the pump and probe pulses temporally overlap in tlie sample, however, all possible time orderings of field-molecule interactions contribute to the response and complicate the interpretation. Double-sided Feymuan diagrams, which provide a pictorial view of the density matrix s time evolution under the action of the laser pulses, can be used to detenuine the various contributions to the sample response [125]. [Pg.1980]

The following sections give an overview of the functional form of the PFF and a short explanation of the various contributions to the total force field energy of a molecule or molecular system. [Pg.340]

VVe can now start to separate the integral in Equation (2.74) into individual terms and identify the various contributions to the electronic energy ... [Pg.63]

Computational results can be related to thermodynamics. The result of computations might be internal energies, free energies, and so on, depending on the computation done. Likewise, it is possible to compute various contributions to the entropy. One frustration is that computational software does not always make it obvious which energy is being listed due to the dilferences in terminology between computational chemistry and thermodynamics. Some of these differences will be noted at the appropriate point in this book. [Pg.10]

Next come the integral transformations (not shown) and then (Figure 11.13) the various contributions to the second, third and fourth order MPn energies. The... [Pg.200]

Figure 3. Various contributions to the scattered X-ray intensity. The system under consideration is a dilute I2/CCI4 solution. Figure 3. Various contributions to the scattered X-ray intensity. The system under consideration is a dilute I2/CCI4 solution.
A number of points should be noted about the various contributions to the capital cost in Table 2.7. The values are ... [Pg.21]

The various contributions to the energy of a molecule were specified in Eq. (47). However, the fact that the electronic partition function was assumed to be equal to one should not be overlooked. In effect, the electronic energy was assumed to be equal to zero, that is, that the molecule remains in its ground electronic state. In the application of statistical mechanics to high-temperature systems this approximation is not appropriate. In particular, in the analysis of plasmas the electronic contribution to the energy, and thus to the partition function, must be included. [Pg.137]

A quasichemical theory, using ab initio simulation (rPBE functional) to generate data for the computation of the various contributions to the free energy, yields an estimate for the excess chemical potential of water very close to the experimental value. [Pg.415]

To put the various contributions to the modeling of codeposition of particles into perspective, not only must the relevant electrochemical literature be reviewed, but also that in the field of filtration. Theories on the mechanisms of capture and encapsulation of particles during metal deposition have only begun to appear in the last two decades. The scope of this section will be to summarize the models published since 1970, and give the basis for their explanation. (A review of the older work can be found in the Ph.D. thesis of C. Buelens [58].) Let us see review the models in chronological order. [Pg.206]

The overall specific heat of a polymer is given by a combination of the various contributions to the specific heat of longitudinal and transversal phonons. At temperatures below 1K, the linear contribution due to the TLS must be added. [Pg.84]

In Table I we present various contributions to the electromagnetic energy-level shift of 7r p and 7T d atoms. As can be seen from Table I, the calculated values of the electromagnetic shifts for ir p and ir d atoms are close to each other. [Pg.321]

One of the most convincing tests of the AG relationship appeared in the work of Scala et al.92 for the SPC/E model of water,57 which is known to reproduce many of water s distinctive properties in its super-cooled liquid state qualitatively. In this study, the dynamical quantity used to correlate with the configurational entropy was the self-diffusivity D. Scala et al. computed D via molecular dynamics simulations. The authors calculated the various contributions to the liquid entropy using the methods described above for a wide range of temperature and density [shown in Figure 12(a-c)]. [Pg.149]

Adding these various contributions to the peak splitting together, we... [Pg.61]

The Wlc total atomization energy at 0 K of aniline, 1468.7 kcal/mol, is in satisfying agreement with the value obtained from heats of formation in the NIST WebBook 39), 1467.7 0.7 kcal/mol. (Most of the uncertainty derives from the heat of vaporization of graphite.) The various contributions to this result are (in kcal/mol) SCF limit 1144.4, valence CCSD correlation energy limit 359.0, connected triple excitations 31.7, inner shell correlation 7.6, scalar relativistic effects -1.2, atomic spin-orbit coupling -0.5 kcal/mol. Extrapolations account for 0.6, 12.1, and 2.5 kcal/mol, respectively, out of the three first contributions. [Pg.188]

What quantity describes best the totahty of these solute-solvent interactions and how can the various contributions to them be estimated Let the pure solute B be vaporized in an imaginary process to a gas, and let this gas be very dilute, so that it obeys the ideal gas laws. In this condition each particle of the solute (molecule or ion) is very remote from any neighbor and has no environment with which to interact. If B is polyatomic, it does have its internal degrees of freedom, such as bond vibrations and rotation of the particle. [Pg.48]

In chromatographic systems, the various contributions to peak broadening are generally independent. This means that the variance of the system is the sum of the variances from each contribution. Combining this relationship with Equation 1 yields an expression for the system bandwidth ... [Pg.195]

As a consequence of the transformation, the equation of motion depends on three extra coordinates which describe the orientation in space of the rotating local system. Furthermore, there are additional terms in the Hamiltonian which represent uncoupled momenta of the nuclear and electronic motion and moment of inertia of the molecule. In general, the Hamiltonian has a structure which allows for separation of electronic and vibrational motions. The separation of rotations however is not obvious. Following the standard scheme of the various contributions to the energy, one may assume that the momentum and angular momentum of internal motions vanish. Thus, the Hamiltonian is simplified to the following form. [Pg.150]

A theoretical analysis based on shear energy was carried out with the aim of illustrating the mechanism of shear nucleation through a slit channel die in continuous microcellular foam extrusion. The shear energies for different positions and for different experimental conditions were calculated to demonstrate the various contributions to the surface free energy required for bubble nucleation. 14 refs. [Pg.28]

In Other words, AVj measures the drift of AV with time as a consequence of performance degradation. The latter can be due to various reasons loss of activity of electrode materials, increase in ohmic drops, that is, the various contributions to A V with the exception of AE, the magnitude of which is fixed by thermodynamics. As a concise term, AVt can be called instability. [Pg.243]

Before closing this chapter, it is important to emphasize the context in which the transition rate expressions obtained here are most commonly used. The perturbative approach used in the above development gives rise to various contributions to the overall rate coefficient for transitions from an initial state i to a final state i these contributions include the electric dipole, magnetic dipole, and electric quadrupole first order tenns as well contributions arising from second (and higher) order terms in the perturbation solution. [Pg.281]


See other pages where Various Contributions to is mentioned: [Pg.48]    [Pg.420]    [Pg.396]    [Pg.208]    [Pg.400]    [Pg.401]    [Pg.807]    [Pg.128]    [Pg.339]    [Pg.73]    [Pg.755]    [Pg.95]    [Pg.145]    [Pg.224]    [Pg.208]    [Pg.71]    [Pg.385]    [Pg.9]    [Pg.9]    [Pg.242]    [Pg.386]    [Pg.401]    [Pg.87]    [Pg.337]    [Pg.217]    [Pg.37]    [Pg.237]    [Pg.680]   


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Estimating the Various Contributions to

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