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Functionals and functional derivatives

Auto-correlation and Inter-correlation Functions allow a good discrimination between these two types of defects by quantifying the resemblance between the different echoes and their derivatives. [Pg.226]

There are three forms of the Langmuir-Szyszkowski equation, Eq. III-57, Eq. Ill-107, and a third form that expresses ir as a function of F. (n) Derive Eq. III-57 from Eq. Ill-107 and (b) derive the third form. [Pg.93]

The mixed, v t — % notation here has historic causes.) The Schrodinger equation is obtained from the nuclear Lagrangean by functionally deriving the latter with respect to t /. To get the exact form of the Schrodinger equation, we must let N in Eq. (95) to be equal to the dimension of the electronic Hilbert space (viz., 00), but we shall soon come to study approximations in which N is finite and even small (e.g., 2 or 3). The appropriate nuclear Lagrangean density is for an arbitrary electronic states... [Pg.146]

These terms are analogous to those on p. 265 of [7], It will be noted that the symbol c has been reinstated as in Section VI.F, so as to facilitate the order of magnitude estimation in the nearly nonrelativistic limit. We now proceed based on Eq. (168) as it stands, since the transformation of Eq. (168) to modulus and phase variables and functional derivation gives rather involved expressions and will not be set out here. [Pg.166]

This part of our chapter has shown that the use of the two variables, moduli and phases, leads in a direct way to the derivation of the continuity and Hamilton-Jacobi equations for both scalar and spinor wave functions. For the latter case, we show that the differential equations for each spinor component are (in the nearly nomelativistic limit) approximately decoupled. Because of this decoupling (mutual independence) it appears that the reciprocal relations between phases and moduli derived in Section III hold to a good approximation for each spinor component separately, too. For velocities and electromagnetic field strengths that ate nomrally below the relativistic scale, the Berry phase obtained from the Schrddinger equation (for scalar fields) will not be altered by consideration of the Dirac equation. [Pg.168]

Importantly for direct dynamics calculations, analytic gradients for MCSCF methods [124-126] are available in many standard quantum chemistiy packages. This is a big advantage as numerical gradients require many evaluations of the wave function. The evaluation of the non-Hellmann-Feynman forces is the major effort, and requires the solution of what are termed the coupled-perturbed MCSCF (CP-MCSCF) equations. The large memory requirements of these equations can be bypassed if a direct method is used [233]. Modem computer architectures and codes then make the evaluation of first and second derivatives relatively straightforward in this theoretical framework. [Pg.301]

In modem quantum chemistry packages, one can obtain moleculai basis set at the optimized geometry, in which the wave functions of the molecular basis are expanded in terms of a set of orthogonal Gaussian basis set. Therefore, we need to derive efficient fomiulas for calculating the above-mentioned matrix elements, between Gaussian functions of the first and second derivatives of the Coulomb potential ternis, especially the second derivative term that is not available in quantum chemistry packages. Section TV is devoted to the evaluation of these matrix elements. [Pg.409]

In order for Am to be a regular matrix at every point in the assumed region of configuration space it has to have an inverse and its elements have to be analytic functions in this region. In what follows, we prove that if the elements of the components of Xm are analytic functions in this region and have derivatives to any order and if the P subspace is decoupled from the corresponding Q subspace then, indeed. Am will have the above two features. [Pg.717]

Figure 2-108 shows the correspondence between a histogram and the derived empirical energy function for the torsion angle fragment C-N H)-C(H)(H -C. [Pg.111]

A m oleciilar ni echaiiics meih od in HyperChem isdefined by a set of atom types and a functional form for the energy and its derivatives for example. AMHKR. For the. AMBKR method, you may use many different default and iiser-defmed parameter sets. Hyper-... [Pg.196]

The order of continuity of a conforming finite element that only ensures the compatibility of functions across its boundaries is said to be C°. Finite elements that ensure the inter-element compatibility of functions and their derivatives provide a higher order of continuity than C°. For example, the Hermilc element shown in Figure 2.4 which guarantees the compatibility of function values and... [Pg.32]

After the substitution for T from Equation (2.68), dx from Equation (2.70) and global derivatives of shape functions from Equation (2.71) into the elemental stiffness equation (2,.55) we obtain, for the equation corresponding to N[... [Pg.52]

Finite element library subroutines containing shape functions and their derivatives in terms of local coordinates. [Pg.196]

I STORES SHAPE FUNCTIONS AND THEIR DERIVATIVES AT REDUCED INTEGRATION POINTS(SCRATCH FILE)... [Pg.220]

The interpolating function and its derivatives should have as simple an algebraic form as possible consistent with the desired goodness of fit. [Pg.176]

Rubbery materials are usually lightly cross-linked. Their properties depend on the mean distance between cross links and chain rigidity. Cross linking can be quantified by the use of functions derived from graph theory, such as the Rao or molar Hartmann functions. These can be incorporated into both group additivity and QSPR equations. [Pg.315]

In the first chapter, devoted to thiazole itself, specific emphasis has been given to the structure and mechanistic aspects of the reactivity of the molecule most of the theoretical methods and physical techniques available to date have been applied in the study of thiazole and its derivatives, and the results are discussed in detail The chapter devoted to methods of synthesis is especially detailed and traces the way for the preparation of any monocyclic thiazole derivative. Three chapters concern the non-tautomeric functional derivatives, and two are devoted to amino-, hydroxy- and mercaptothiazoles these chapters constitute the core of the book. All discussion of chemical properties is complemented by tables in which all the known derivatives are inventoried and characterized by their usual physical properties. This information should be of particular value to organic chemists in identifying natural or Synthetic thiazoles. Two brief chapters concern mesoionic thiazoles and selenazoles. Finally, an important chapter is devoted to cyanine dyes derived from thiazolium salts, completing some classical reviews on the subject and discussing recent developments in the studies of the reaction mechanisms involved in their synthesis. [Pg.599]

Ultraviolet photoelectron spectroscopy allows the determination of ionization potentials. For thiazole the first experimental measurement using this technique was preformed by Salmona et al. (189) who later studied various alkyl and functional derivatives in the 2-position (190,191). Substitution of an hydrogen atom by an alkyl group destabilizes the first ionization potential, the perturbation being constant for tso-propyl and heavier substituents. Introduction in the 2-position of an amino group strongly destabilizes the first band and only slightly the second. [Pg.51]

The first mass spectrometric investigation of the thiazole ring was done by Clarke et al. (271). Shortly after, Cooks et al., in a study devoted to bicydic aromatic systems, demonstrated the influence of the benzo ring in benzothiazole (272). Since this time, many studies have been devoted to the influence of various types of substitution upon fragmentation schemes and rearrangements, in the case of alkylthiazoles by Buttery (273) arylthiazoles by Aune et al. (276), Rix et al. (277), Khnulnitskii et al. (278) functional derivatives by Salmona el al. (279) and Entenmann (280) and thiazoles isotopically labeled with deuterium and C by Bojesen et al. (113). More recently, Witzhum et al. have detected the presence of simple derivatives of thiazole in food aromas by mass spectrometry (281). [Pg.81]

In the preceding chapter the special stability of benzene was described along with reac tions in which an aromatic ring was present as a substituent Now we 11 examine the aromatic ring as a functional group What kind of reactions are available to benzene and Its derivatives What sort of reagents react with arenes and what products are formed m those reactions ... [Pg.473]

As we have seen in this chapter steroids have a number of functions in human physiology Cholesterol is a component part of cell mem branes and is found in large amounts in the brain Derivatives of cholic acid assist the digestion of fats in the small intestine Cortisone and its derivatives are involved in maintaining the electrolyte balance in body fluids The sex hormones responsible for mascu line and feminine characteristics as well as numerous aspects of pregnancy from conception to birth are steroids... [Pg.1099]

We desire to use the probability function derived above, so we recognize that the mass contribution of the volume element located a distance r from an axis through the center of mass is the product of the mass of a chain unit mp times the probability of a chain unit at that location as given by Eq. (1.44). For this purpose, however, it is not the distance from the chain end that matters but, rather, the distance from the center of mass. Therefore we temporarily identify the jth repeat unit as the center of mass and use the index k to count outward toward the chain ends from j. On this basis, Eq. (1.49) may be written as... [Pg.53]

Proof. First of all we And the derivative of the functional J. It is easily seen that... [Pg.31]


See other pages where Functionals and functional derivatives is mentioned: [Pg.163]    [Pg.163]    [Pg.132]    [Pg.266]    [Pg.44]    [Pg.174]    [Pg.66]    [Pg.2420]    [Pg.256]    [Pg.313]    [Pg.13]    [Pg.152]    [Pg.326]    [Pg.249]    [Pg.631]    [Pg.21]    [Pg.54]    [Pg.328]    [Pg.81]    [Pg.462]    [Pg.82]    [Pg.168]    [Pg.204]    [Pg.310]    [Pg.50]    [Pg.213]    [Pg.220]    [Pg.210]    [Pg.252]    [Pg.276]   
See also in sourсe #XX -- [ Pg.132 ]




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