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Logarithmic derivatives correspondence

Incidentally we can limit ourselves to real energies, identifying, in the limit to the real axis and the unique bound state solution alternatively the two branches in the continuum, while if the energy is complex we must keep in mind that/+ (k, r) correspond to a unique square integrable solutions if I (k) > 0 and/ (k, r) if I(k) < 0, where I(k) denotes the imaginary part of k. In the case of logarithmic derivative obtains two branches corresponding to the limits e -> 0... [Pg.44]

Fig. 31 The logarithmic derivative of the resistivity with respect to T 1 versus temperature as a function of impurity doping for samples of TSeF, TTF/TCNQ 0> x = 0 , x = 0.003 A, x = 0.0125 0, x = 0.025. The maxima at ca. 28 K and ca. 36 K correspond to the phase transitions. (After Craven etal., 1977)... Fig. 31 The logarithmic derivative of the resistivity with respect to T 1 versus temperature as a function of impurity doping for samples of TSeF, TTF/TCNQ 0> x = 0 , x = 0.003 A, x = 0.0125 0, x = 0.025. The maxima at ca. 28 K and ca. 36 K correspond to the phase transitions. (After Craven etal., 1977)...
In a very different context, in statistical mechanics theory of critical phenomena, corrections to classical exponents are calculated using a systematic series of mean field approximations. In this case, the deviation r from the mean-field value of a critical exponent is called coherent anomaly [173], Remember that ER(X) in Eqs. (115)—(118) corresponds to a bound state if XR < Xc and corresponds to a virtual state if XR >XC. Note that there is no other formal difference between bound and virtual states other than the sign in the logarithmic derivate of the wave function at r = R. Therefore there are no technical problems related with this fact. A relation between XR and Xc can be established for compact support potentials. In this case, using variational arguments, we obtain... [Pg.67]

Figure 11. Dirac logarithmic derivatives for k=— — 1 (D ) and (D+), together with De, the corresponding "scalar relativistic logarithmic derivative. The figure illustrates the effects of SO coupling and how the spin-orbit parameter varies across the band. Bonding states B) are at the band bottom, antibonding (i4) at the top. Note that W- >Wt> W+, and that... Figure 11. Dirac logarithmic derivatives for k=— — 1 (D ) and (D+), together with De, the corresponding "scalar relativistic logarithmic derivative. The figure illustrates the effects of SO coupling and how the spin-orbit parameter varies across the band. Bonding states B) are at the band bottom, antibonding (i4) at the top. Note that W- >Wt> W+, and that...
In 1973 Andersen and Woolley [1.25] extended the LCMTO method to molecular calculations. At the end of their paper they introduced that choice of MTO tail, i.e. proportional to J = 9i/j/9E, which in a natural fashion ensured orthogonality to the core states and at the same time led to an accurate and elegant formulation of linear methods. The resulting, technique was immediately developed in a paper by Andersen [1.26] which, in a condensed form, contains most of what one need know about the simple concepts of linear band theory. Thus, we find here the KKR equation within the atomic-sphere approximation at this stage is called ASM the LCMTO secular matrix, latter called the LMTO matrix the energy-independent structure constants and the canonical bands and the Laurent expansion of the logarithmic-derivative function and the corresponding potential parameters. [Pg.21]

The corresponding radial logarithmic derivatives at the sphere boundary are... [Pg.292]

With later use in mind we now proceed to establish relations between the value of the u th energy derivative function V(S) at the sphere, the corresponding logarithmic derivative D < >, and the integral in the sphere. [Pg.293]

The logarithmic derivative of linearly independent solutions of the coupled C( uations (11) arc propagated outwards in each sector [pp-i/2Q- p+i/2] using the Jolmson-Manolopoulos [8] algorithm. At the boundary of each sector / p+i/2, a transformation to the basis of the next sector [Pp+i/2-, Pp+ipi] computed at Pp+i is performed. This is repeated until the last sector (centered at / , ) corresponding to the asymptotic region is readied. [Pg.191]

Figure 4 Scattered light correlation functions for the AOT system at different distances from the critical point, from 0.07° (top curve) to 2.55° (bottom curve). The curves are fits with the droplet model (see Appendix). The corresponding values of the first cumulant T are given after AT F can be calculated by taking the t = 0 limit of the logarithmic derivative of C(t). (Data from Refs. 31 and 32.)... Figure 4 Scattered light correlation functions for the AOT system at different distances from the critical point, from 0.07° (top curve) to 2.55° (bottom curve). The curves are fits with the droplet model (see Appendix). The corresponding values of the first cumulant T are given after AT F can be calculated by taking the t = 0 limit of the logarithmic derivative of C(t). (Data from Refs. 31 and 32.)...
The radial Schrodinger equations are solved for each sort of atoms and from the matching conditions at the s—spheres of the i—th component, of radii s j, and o-spheres we set up the backwards extrapolated free-electron solutions and the corresponding logarithmic derivatives... [Pg.343]

The data are also represented in Fig. 39.5a and have been replotted semi-logarithmically in Fig. 39.5b. Least squares linear regression of log Cp with respect to time t has been performed on the first nine data points. The last three points have been discarded as the corresponding concentration values are assumed to be close to the quantitation limit of the detection system and, hence, are endowed with a large relative error. We obtained the values of 1.701 and 0.005117 for the intercept log B and slope Sp, respectively. From these we derive the following pharmacokinetic quantities ... [Pg.460]

An obvious difficulty arises with this rather elaborate rationale when phosphoramidate and aryl phosphoramidate monoanions are compared for example, the dissimilarity of the dioxan effect yet the identity of product distribution observed in methanol-water competition experiments. Preliminary studies in the author s laboratory have revealed striking differences in the hydrolytic behavior between a series of phosphoramidafes derived from primary aliphatic amines and the above aryl systems. No linear structure-reactivity relationship between the logarithmic rate of hydrolysis of the monoanion species and the pKa of the amine is observed19. Moreover, the rate of hydrolysis of phosphoramidate monoanions derived from aliphatic amines is at least 104 times slower than those formed from aryl amines. In contrast, only a thirtyfold decrease in rate is observed for the corresponding ApKa in the O-phos-phate monoester series. The suspicion that mechanism (1), even with the above proposed modification, is not an accurate description of phosphoramidate monoanion hydrolysis derives some further support from the observation that the monoanion is subject to nucleophilic attack by substituted pyridines al-... [Pg.4]

Only a few electrophilic reactions of selenolopyridines have been reported. In deuteriodeprotonation of selenolo[3,2-6]pyridine the 3-position is the preferred site of attack (78JCS(P2)86l>. In selenolo[3,2-6]pyridine and thieno[3,2-6]pyridine the C-2/C-3 reactivity ratio is ca. 10-3 whereas for furo[3,2-6]pyridine a value of ca. 10-5 has been determined. Logarithmic partial rate factors (Figure 13) show that seleno o[3,2-6 ]pyridine is the most reactive compound. As in the case of (9) and (261), the deuteriodeprotonation of (426) takes place on the protonated species. Both se enolo[2,3-6]- and [3,2-6]pyridine (423, 426) on treatment with potassium nitrate and concentrated sulfuric acid give yield the corresponding 3-nitro derivatives in 50% yield (10 °C, 3 h). [Pg.1035]

The substituent constant of the Hammett equation has been related successfully to the logarithm of the activity coefficient ratio at infinite dilution for a series of meta and para isomers of phenol. Hammett stated that a free energy relationship should exist between the equilibrium or rate behavior of a benzene derivative and a series of corresponding meta and para monosubstitut-ed benzene derivatives. The Hammett equation may be written... [Pg.566]

We have already seen an example of how to calculate the derivative of inverse functions when dealing with fractional powers. In the case of the exponential function the corresponding inverse is the logarithmic function y = ln(x). Its derivative follows from Eq. (25) ... [Pg.117]


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See also in sourсe #XX -- [ Pg.552 , Pg.553 , Pg.554 ]

See also in sourсe #XX -- [ Pg.552 , Pg.553 , Pg.554 ]




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