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Indicator function derivatives

It turns out that, for this model, the indicated functional derivative is already symmetric. [Pg.231]

Indicator functions are based upon an analysis of either the eigenvalues or the errors. Some of them have been derived empirically, while others are... [Pg.103]

In the study of reactivity, Jorgensen and col. have normally used both, the OPLS model and potential functions derived from ab initio calculations. As we have already indicated, when intermolecular pair potentials are applied to the study of a chemical process, the evolution of charges, as well as the Lennard-Jones terms, along the reaction coordinate, has to be considered. For the SN2 reaction in water between chloride anion... [Pg.160]

Types of compounds are arranged according to the following system hydrocarbons and basic heterocycles hydroxy compounds and their ethers mercapto compounds, sulfides, disulfides, sulfoxides and sulfones, sulfenic, sulfinic and sulfonic acids and their derivatives amines, hydroxylamines, hydrazines, hydrazo and azo compounds carbonyl compounds and their functional derivatives carboxylic acids and their functional derivatives and organometallics. In each chapter, halogen, nitroso, nitro, diazo and azido compounds follow the parent compounds as their substitution derivatives. More detail is indicated in the table of contents. In polyfunctional derivatives reduction of a particular function is mentioned in the place of the highest functionality. Reduction of acrylic acid, for example, is described in the chapter on acids rather than functionalized ethylene, and reduction of ethyl acetoacetate is discussed in the chapter on esters rather than in the chapter on ketones. [Pg.321]

From this equation it follows that dg,A Pa is diagonal in the spin indices. We will therefore in the following put density variation 5p (r) determines the potential variation 5vs,(r) only up to a constant (see also [66] ). To find an explicit expression for the above functional derivative we must find an expression for the inverse density response function i A. In order to do this we make the following approximation to the Greens function (see Sharp and Horton [39], Krieger et al. [21]) ... [Pg.128]

The joint solution is p = 3.2301 and a = 2.9354. It might not seem obvious, but we can also derive asymptotic standard errors for these estimates by constructing them as method of moments estimators. Observe, first, that the two estimates are based on moment estimators of the probabilities. Let x, denote one of the 500 observations drawn from the normal distribution. Then, the two proportions are obtained as follows Let z,(2.1) = l[x, < 2.1] and z,(3.6) = l[x, < 3.6] be indicator functions. Then, the proportion of 35% has been... [Pg.96]

Figure 1 The colour index Exj-b as a function of Ein the filter system of Johnson (1966). The indices as derived from a Planck function (BB thin line), those as observed by Menzieset al. (1987) without (dots with numbers) and including interstellar reddening correction (A y = 0.08...0.18 mag. Wampler et al., 1987 bars), and those as calculated (open circles) by the models I-VI (see table 1) are given. Figure 1 The colour index Exj-b as a function of Ein the filter system of Johnson (1966). The indices as derived from a Planck function (BB thin line), those as observed by Menzieset al. (1987) without (dots with numbers) and including interstellar reddening correction (A y = 0.08...0.18 mag. Wampler et al., 1987 bars), and those as calculated (open circles) by the models I-VI (see table 1) are given.
Compounds 14-17 are derivatives of the corresponding silanes 10 and 12. Functional pharmacological studies (Ml-M3 receptors) and radioligand binding experiments (M1-M4 receptors) with the pure (/ )- and (S )-enantiomers of these compounds revealed very similar pA2 values as observed for the antipodes of the related analogues 10 and 1234. The highest stereoselectivity indices (functional studies) were determined for 17 [SI = 44 (Ml), 7.6 (M2), 20 (M3)]. [Pg.2374]

The relative Michael-acceptor abilities of a variety of substituted aromatic and aliphatic nitroalkenes have been elucidated by computational methods. Several global and local reactivity indices were evaluated with the incorporation of the natural charge obtained from natural bond orbital (NBO) analysis. Natural charges at the carbon atom to the NO2 group and the condensed Fukui functions derived by this method were found to be consistent with the reactivity.187... [Pg.353]

Euler-Euler models assume interpenetrating continua to derive averaged continuum equations for both phases. The probability that a phase exists at a certain position at a certain time is given by a phase indicator function, which, for steady-state processes, is equivalent to the volume of fraction of the correspondent phase (volume-of-fluid technique). The phase-averaging process introduces further unknowns into the basic conservation equations their description requires empirical and problem-dependent input (94). In principal, Euler-Euler models are applicable to all multiphase flows. Advantages and disadvantages of both methods are compared, e.g., in Refs. 95 and 96. [Pg.338]

Here ak and a, are creation and annihilation operators, and hk(ri) are mode functions that satisfy (a) the normalization condition hkhk — h kh k = % (a prime indicates a derivative with respect to conformal time), and (b) the mode... [Pg.298]

This formula was used by Slater [385] to define an effective local exchange potential. The generally unsatisfactory results obtained in calculations with this potential indicate that the locality hypothesis fails for the density functional derivative of the exchange energy Ex [294],... [Pg.72]

Functional derivatives are indicated here because aq may be a parametric field, as for example a Lagrange multiplier field. Variations of aq determine J11 = Jq daq, where... [Pg.187]

The NICS of each ring, as a criterion of aromaticity, has been used to explain the stability order of benzo[/)]thio-phene and its isomer. The results indicate that the benzene ring is aromatic in all the systems. The five-membered ring of benzo[. ]thiophene is also aromatic, whereas in benzo[r]thiophene it is nonaromatic. This could be an explanation of the stability of the former molecule. The MOS and the condensed Fukui functions derived from the electronic-structure calculations explain the expected electrophilic substitution of these compounds. The theoretical structure, ionization energies, order of aromaticity, stability, and reactivity are in good agreement with the experimental results <2003T6415>. [Pg.694]


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